计算机专业英语

主讲人 : 肖 鸿

二 0 一 0 年十月

司法信息安全教研室

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计算机专业英语计算机专业英语Computer Specialized EnglishComputer Specialized English

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objective

To study computer principles, fundamentals, and new development in this field; To learn computer terminology, to be familiar with the style, the grammar and the

characteristics of Computer English; To improve one’s reading, writing and translation ability, so that he/she can read some

English newspapers, magazines or books on computer easily, and lay a solid foundation for further study.

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内 容 简 介 (Content)

1 、介绍计算机专业英语的基础知识，包括专业英语中的词汇特点以及阅读与翻译计算机专业资料的方法、技巧；

2 、介绍计算机硬件知识 (hardware) ，包括计算机硬件基础 (hardware fundamentals) 、处理器 (processor) 、存储器 (memory) 、输入 / 输出设备 (input/output device) 及计算机并行系统 (computer parallel system) 。

3 、计算机软件知识部分 (software) ，内容有数据结构 (data structure) 、操作系统 (operating system) 、程序设计语言 (programming language) 、软件工程 (software engineering) 及软件测试与维护 (software testing and maintenance) 知识；

4 、计算机网络 (computer network) 相关知识介绍，包括计算机网络基础知识、 OSI 参考模型、互联网技术、网络安全及电子商务；

5 、计算机应用方面的知识，内容有文字处理技术、多媒体技术、计算机图形学、数据库应用及计算机病毒。

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How to learn

Key: to be familiar with the characteristics To be familiar with word(phrase)-formation/word-building Word/phrase accumulation To improve reading ability consciously

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第 1 章 计算机专业英语基础知识

1.1 专业英语的专业性和客观性 1.2 计算机专业英语的词汇特点 1.3 计算机专业文献的阅读与翻译

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1.1 专业英语的专业性和客观性

专业英语的特点 专业英语的专业性和客观性 英语的句子成分简介

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计算机专业英语概述

科技文章属于严肃的书面语体，崇尚严谨周密，逻辑性强，要求层次分明，重点突出。 各个领域的专业英语都以表达科技概念、理论和事实为主要目的，因此，它们很注重客

观事实和真相，要求逻辑性强，条理规范，表达准确、精练以及正式。

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计算机专业英语概述

计算机专业术语多，而且派生和新出现的专业用语还在不断地增加。 在表达形式上，计算机专业英语与普通英语一样都有口语和书面形式两种。口语形式大

多出现在一些专业知识的讲座、广播等场合中，而书面形式一般是一些书籍、论文和杂志等，用语正规。

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计算机专业英语概述

在文体结构上，由于专业英语大多强调简单明了、精练准确，所以会大量地使用一些诸如动名词、分词和不定式等非限定性动词。

在语气上，大量使用被动语态是专业英语的一大特色。 专业英语中所使用的时态有 60% 以上是一般现在时，有大约 5% 左右是一般过去时，

所以在翻译过程中，就要用一些能突出英语句子中对时态表达的词。

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专业英语的特点

科学技术本身的性质要求专业英语与专业内容相互配合，相互一致，这就决定了专业英语 （ English for Special Science and Technology ） 与 普 通 英 语 （ Common English or General English ）有很大的差异。

专业英语的主要特点是它具有很强的专业性，懂专业的人用起它来得心应手，不懂专业的人用起来则困难重重。

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专业英语在词汇短语和句子结构方面的特点

合成新词多、专业术语多、介词短语多及半技术词汇多 , 缩略词经常出现 (special terms, abbreviations, derivatives, etc.)

旧词新意 (old words often take on new meanings):bus, thread, exception, versatility, fault)

时 效 性 (time-efficiency): procedural programming, object-oriented programming, object-relational programming, UML, HTML, XML, MVC)

长句多 (long sentence) 被动语态使用频繁 (passive voice) 用虚拟语气表达假设或建议 常用 It … 句型结构 常使用动词或名词演化成的形容词 在说明书、手册中广泛使用祈使语句 插图、插画、表格、公式、数字所占比例大

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专业文体的语法特点

时态：时态形式使用比较单一，最常用的有五种时态，即一般现在时、现在进行时、一般过去时、一般将来时和现在完成时。

语态：经常使用被动语态，而且多为没有行为的被动语态。 谓语：经常使用静态结构，用来表示状态或情况。 定语：经常使用名词做定语，以取得简洁的效果。 如用 radar range-finder target selector switch 表达雷达测距目标选择开关。 动词非限定形式：经常使用它们来扩展句子，如动词不定式短语、动名词短语、分词短

语及独立分词结构。

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专业文体的语法特点

名词化：以名词为中心词构成短语以取代句子，如句子 when the experiment has been completed可改写成名词短语 on completion of the experiment 。

多重复合句：长复合句较多，句子中又嵌入句子。 逻辑词语：使用很频繁，明确表示出内容的内在联系，有助于清楚地叙述、归纳、推理 、 论证和 概括。 如 hence ， consequently ， as a result ， therefore, thus, although, however, at the same time, on the other hand, nevertheless ，on the contrary ， in short ， as mentioned above 等。

叙述方式：常避免用第一人称单数，而用第一人称复数 we ，或用 the author 等第三人称形式。

句子含义直接 (The meaning of the word or sentence is direct, no story, no plot, no connotation, only facts)---tedious/boring

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专业英语的专业性与客观性

由于科学技术关心的不是个人的心理情绪，而是客观的普遍规律和对过程、概念的描述，因此专业英语应具有的客观性和无人称性（ Objectivity and Impersonality ）必然要反映到语法结构上来。

专业英语文体在很多情况下是对某个科学论题的讨论，介绍某个科技产品和科学技术，为了表示一种公允性和客观性，往往在句子结构上采用被动语态描述，即以被描述者为主体，或者以第三者的身份介绍文章要点和内容。

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专业性与客观性的体现

因为专业英语的客观性，所以在文章中常用被动语态。有人统计专业英语中被动语态的句子要占 1/31/2 。即使用主动语态，主语也常常是非动物的（ inanimate subject ）。

就时态而言，因为专业科技文献所涉及的内容（如科学定义、定理、方程式或公式、图表等）一般并没有特定的时间关系，所以在专业英语中大部分都使用一般现在时。

因为要求精练，专业英语中常希望用尽可能少的单词来清晰地表达原意。这就导致了非限定动词、名词化单词或词组及其他简化形式的广泛使用。

专业英语的准确性主要表现在用词上。然而在语法结构上也有其特点。例如，为了准确精细地描述事物过程，所用句子都较长有些甚至一段就是一个句子。

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计算机专业英语中长句的运用

长句主要是由于修饰语过多、并列成分多及语言结构层次多等因素造成的。如名词后面的定语短语或定语从句，以及动词后面或句首的介词短语或状语从句。这些修饰成分可以一个套一个连用（包孕结构），形成长句结构。

在专业文章中，长句往往是对技术的关键部分的叙述，翻译的不恰当就会造成整个段落甚至通篇文章都不清楚。

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分析长句时采用的方法

找出全句的基本语法成份，即主语、谓语和宾语，从整体上把握句子的结构。 找出句子中所有的谓语结构、非谓语动词、介词短语和从句的引导词等。 分析从句和短语的功能，即是否为主语从句、宾语从句、表语从句等，若是状语从句，

则分析它是属于时间状语从句、原因状语从句、条件状语从句、目的状语从句、地点状语从句、让步状语从句、方式状语从句、结果状语从句，还是比较状语从句。

分析词、短语和从句之间的相互关系，如定语从句修饰的先行词是哪一个等。 注意分析句子中是否有固定词组或固定搭配。 注意插入语等其他成份。

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阅读和翻译英语长句的方法

顺序法：当英语长句的内容叙述层次与汉语基本一致时，或英语长句中所描述的一连串动作是按时间顺序安排的，可以按照英语原文的顺序翻译成汉语。

逆序法：所谓逆序法就是从长句的后面或中间译起，把长句的开头放在译文的结尾。这是由于英语和汉语的表达习惯不同：英语习惯于用前置性陈述，先结果后原因；而汉语习惯则相反，一般先原因后结果，层层递进，最后综合。

分句法：有时长句中主语或主句与修饰词的关系并不十分密切，翻译时可以按照汉语多用短句的习惯，把长句的从句或短语化成句子，分开来叙述。而有时英语长句包含多层意思，而汉语习惯于一个小句表达一层意思。为了使行文简洁，翻译时可把长句中的从句或介词短语分开叙述，顺序基本不变，保持前后的连贯。

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专业文体的语法特点

A computer is an electronic device that can receive a set of instructions, or program, and then carry out this program by performing calculations on numerical data or by manipulating other forms of information.

A computer is a fast and accurate symbol manipulating system that is organized to accept, store, and process data and produce output results under the direction of a stored program of instructions.

Different types and sizes of computers find uses throughout society in the storage and handling of data, from secret governmental files to banking transactions to private household accounts.)

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被动语态在计算机专业英语中的应用

被动语态表示主语是谓语动作的承受者。 被动语态在科技文章中用得十分频繁，主要有两个原因。第一个原因是科技文章

重在描写行为或状态本身，所以由谁或由什么作为行为或状态的主体就显得不重要。行为或状态的主体或者没有必要指出，或者根本指不出来。被动语态使用频繁的第二个原因是便于向后扩展句子，避免句子头重脚轻和不平衡。下面介绍科技英语中主要时态的被动语态形式。

It is organized/designed to It was developed/proposed by …, for the purpose of Database services and computer networks make available a great variety

of information sources. The same advanced techniques also make possible invasions of personal

and business privacy.

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一般现在时

一般现在时的被动语态构成如下：主语 + am （ is ， are ） + 及物动词的过去分词例： The switches are used for the opening and closing of electrical circuits.

译文：开关是用来开启和关闭电路的。

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一般过去时

一般过去时的被动语态构成如下：主语 + was （ were ） + 及物动词的过去分词例： That plotter was not bought in Beijing.

译文：那台绘图仪不是在北京买的。

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一般将来时

一般将来时的被动语态构成如下：主语 + will be + 及物动词的过去分词当主语是第一人称时，可用：主语 + shall be + 及物动词的过去分词例： I shall not be allowed to do it.

译文：不会让我做这件事的。例： What tools will be needed for the job?

译文：工作中需要什么工具？

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现在进行时

现在进行时的被动语态构成如下：主语 + is （ are ） being + 及物动词的过去分词例： Electron tubes are found in various old products and are still being used in the circuit of some new products.

译文：在各种老产品里看到的电子管，在一些新产品的电路中也还在使用。

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过去进行时

过去进行时的被动语态构成如下：主语 + was （ were ） being + 及物动词的过去分词例： The laboratory building was being built then.

译文：实验大楼当时正在建造。

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现在完成时

现在完成时的被动语态构成如下：主语 + have （ has ） been + 及物动词的过去分词例： The letter has not been posted.

译文：信还没有寄出。例： The virus in the computer has been found out.

译文：计算机中的病毒已经找出来了。

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过去完成时

过去完成时的被动语态构成如下：主语 + had been + 及物动词的过去分词例： When he came back, the problem had already been solved.

译文：他回来时，问题已经解决了。

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英语的句子成分简介——主语（ Subject ）

主语是句子的主体，是句子所要说明的人或事物。主语通常是一些代表事物性或实体性的问语。除了名词可担任主语外，还有代词、数词、动词不定式、动名词、从句均可做主语。例： She works in a big company.

译文：她在一家大公司工作。

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英语的句子成分简介——谓语（ Predicate ）

谓语说明主语“做什么”、“是什么”或“怎么样”。例： They decided not to sell their computers.

译文：他们决定不卖掉他们的计算机。

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英语的句子成分简介——宾语（ Object ）

宾语表示动作的对象，是主语的动作的承担者，有宾语的动词称为及物动词，宾语一般在及物动词之后，作宾语的词有名词、代词宾格、数词、动词不定式、动名词、复合结构、从句等。例： They have already finished the work.

译文：他们已经完成了那项工作。

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英语的句子成分简介——定语（ Attribute ）

定语是用来修饰名词或代词的。除形容词外，数词、名词所有格、动词不定式、介词短语、分词短语、动名词、副词和从句等，都可以作定语。例： There is some exciting news on the newspaper today.

译文：今天报上有令人兴奋的消息。

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英语的句子成分简介——状语（ Adverbial ）

状语是用来修饰动词、形容词、副词的，表示时间、地点、原因、方式、程度等。作状语的词有副词或相当于副词的其他词、短语和从句。例： There is a printer in the room.

译文：房间里有一台打印机。

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英语的句子成分简介——补语（ Complement ）

英语中有些及物动词虽然有了宾语，但句子的意思仍不完整，还需要在宾语之后增加一个成分以补足其意义，这种成分叫宾语补语。能作宾语补语的有名词、形容词、介词短语、副词、动词不定式和分词等。例： They believe this printer to be the best.

译文：他们相信这台打印机是最好的。

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英语的句子成分简介——同位语（ Appositive ）

同位语用来对一个词或词组的内容加以补充和说明。它通常位于其说明的词或词组之后。例： Our teacher, Mr. Smith, has developed a kind of new software.

译文：我们老师，史密斯先生，已经开发了一种新软件。例： We Chinese are working hard to make our country rich and strong.

译文：我们中国人民正努力工作使我们的国家富强起来。

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英语的句子成分简介——插入语

插入语通常是对一句话作一些附加的解释。常用来作这类附加成分的结构有： I think ， I hope ， I suppose ， I guess ， you know ， don’t you think ， it seems ， you see ，it is said ， it is suggested 等。它们一般放在句子末尾，也可放在句子中间。例： Her design, I think, is the best of all.

译文：我认为她的设计是最好的。例： This is the best printer in this company, I suppose.

译文：我想这是这个公司最好的打印机。

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1.2 计算机专业英语的词汇特点

专业英语词汇的构成特点 词汇缩略 计算机专用术语与命令 专业英语中常用的符号和数学表达式

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专业英语词汇的构成特点

词汇是构成句子的元素，学习和研究语言必须掌握一定的词汇，词汇是阅读、翻译和写作的基础。

随着科学技术的发展，新术语、新概念、新理论和新产品不断出现。 在专业英语中，缩略词的增加尤其迅速，各类技术词汇也随着专业的细分、学科的渗透

而日益增多。

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计算机专业英语中常见的词汇分类方法

技术词汇（ technical words ） 次技术词汇（ sub-technical words ） 特用词（ big words ） 功能词（ function words ）

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技术词汇

这类词的意义狭窄、单一，一般只使用在各自的专业范围内，因而专业性很强。这类词一般较长并且越长词义越狭窄，出现的频率也不高。

例如： bandwidth （ 带 宽 ） ， flip-flop （ 触 发 器 ） ， superconductivity （ 超 导

性）， hexadecimal （十六进制）， amplifier （放大器）等。

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次技术词汇

次技术词汇是指不受上下文限制的各专业中出现频率都很高的词。这类词往往在不同的专业中具有不同的含义。 例如： register 在计算机系统中表示寄存器，在电学中表示计数器、记录器，在乐器中表示音区，而在日常生活中则表示登记簿、名册、挂号信等。

·42·23/4/21 计算机专业英语 42

特用词

在日常英语中，为使语言生动活泼，常使用一些短小的词或词组。而在专业英语中，表达同样的意义时，为了准确、正式、严谨，不引起歧义却往往选用一些较长的特用词。这些词在非专业英语中极少使用但却属于非专业英语。日常英语中常用下列句子：Then the light is turned on.

在专业英语中，却表示为：The circuit is then completed.

这是由于 complete 词义单一准确，可以避免歧义。而 turned on 不仅表示开通，而且还可以表示其他意义，如：The success of a picnic usually turns on （依赖） the weather.

·43·23/4/21 计算机专业英语 43

功能词

它包括介词、连词、冠词、代词等。功能词为词在句子中的结构关系提供了十分重要的结构信号，对于理解专业内容十分重要，而且出现频率极高。研究表明，在专业英语中，出现 频 率 最 高 的 十 个 词 都 是 功 能 词 ， 其 顺 序 为 ：the ， of ， in ， and ， to ， is ， that ， for ， are ， be 。下例中 14 个词中功能词就占了 5 个。When the recorder is operated in the record mode, previous recordings are automatically erased.

译文：当录音机工作在录音模式时，以前的录音被自动擦除。

·44·23/4/21 计算机专业英语 44

计算机专业英语的构词方法

大部分专业词汇来自希腊语和拉丁语；前缀和后缀的出现频率非常高。 希腊语和拉丁语是现代专业英语词汇的基础。各行各业都有一些自己领域的专业词汇，

有的是随着本专业发展应运而生的，有的是借用公共英语中的词汇，有的是借用外来语言词汇，有的则是人为构造成的词汇。

·45·23/4/21 计算机专业英语 45

合成词（ composition ）

合成词（也称复合词）是专业英语中另一大类词汇，其组成面广，多数以短划线“ -”连接单词构成，或者采用短语构成。

合成方法有名词 + 名词，形容词 + 名词，动词 +副词，名词 + 动词，介词 + 名词，形容词 + 动词等等。

但是合成词并非随意可以构造，否则会形成一种非正常的英语句子结构，虽然可由多个单词构成合成词，但这种合成方式太冗长，应尽量避免。

·46·23/4/21 计算机专业英语 46

有短划线“ -”连接的合成词

file + based file-based 基于文件的Windows + based Windows-based 以 Windows 为基础的object + oriented object-oriented 面向对象的thread + oriented thread-oriented 面向线程的point + to + point point-to-point 点到点

·47·23/4/21 计算机专业英语 47

有短划线“ -”连接的合成词

plug + and + play plug-and-play 即插即用point+and+click point-and-click 点击store-and-forward store-and-forward 储转发peer + to + peer peer-to-peer 对等的front + user front-user 前端用户end + user end-user 终端用户push + up push-up 上拉pull + down pull-down 下拉line + by + line line-by-line 逐行

·48·23/4/21 计算机专业英语 48

有短划线“ -”连接的合成词

paper + free paper-free 无纸的jumper + free jumper-free 无跳线的user + centric user-centric 以用户为中心的wave + length wave-length 波长medium + sized medium-sized 中型的

·49·23/4/21 计算机专业英语 49

合成词的各部分构词成分分开写

bus + stop bus stop 汽车站machine +building machine building 机器制造book + learning book learning 书本知识building + material building material 建筑材料swimming + pool swimming pool 游泳池off + hand off hand 即刻的

·50·23/4/21 计算机专业英语 50

省略合成词中间的连接符而形成独立单词

in + put input 输入out + put output 输出feed + back feedback 反馈work + shop workshop 车间fan + in fanin 扇入fan + out fanout 扇出out + come outcome 结果on + line online 在线key+board keyboard

类似： download upload videotape

·51·23/4/21 计算机专业英语 51

派生词（ derivation ）

专业英语词汇大部分都是用派生法构成的，它是根据已有的词，通过对词根加上各种前缀和后缀来构成新词。

如果较好地掌握了构词的三要素：前缀、词根和后缀的话，你的词汇运用能力就会得到很大提高。

这些前缀有名词词缀，如： inter- ， sub- ， in- ， tele- ， micro- 等；形容词词缀，如： im- ， un- 等；动词词缀，如： re- ， under- ， de- ， con- 等。其中，采用前缀构成的单词在计算机专业英语中占了很大比例。

后缀是指在单词后部跟上构词结构，形成新的单词，如 -able ， -al ， -ing ， -ed ， -meter ， -ware ， -en 等。

·52·23/4/21 计算机专业英语 52

典型的派生词

（ 1 ） multi- 多，多的multimedia 多媒体 multiprocessor 多处理器multiprogram 多道程序 multiplex 多路复用（ 2 ） hyper- 超级hypertext 超文本 hypermedia 超媒体hyperswitch 超级交换机 hypersonic 超音速的（ 3 ） super- 超级supertanker 超级油轮 superstate 超级大国superstructure 上层建筑 superuser 超级用户（ 4 ） tele- 远程的， 电的telephone 电话 teleconference 远程会议telescope 望远镜 telegraph 电报

·53·23/4/21 计算机专业英语 53

典型的派生词

（ 5 ） micro- 微型microprocessor 微处理器 microcode 微代码microcomputer 微型计算机 microwave 微波（ 6 ） inter- 相互，在 …… 之间interface 接口 internet 互联网interlace 隔行扫描 interlock 联锁（ 7 ） re- 再，重新rerun 重新运行 rewrite 改写resetup 重新设置 reprint 重新打印（ 8 ） semi- 半semiconductor 半导体 semiautomatic 半自动的semidiameter 半径 semicircular 半圆的

·54·23/4/21 计算机专业英语 54

典型的派生词

（ 9 ） ultra- 超过，极端ultrashort 超短（波）的 ultrared 红外线的ultraspeed 超高速的 ultramicroscope 超显微镜（ 10 ） un- 反，不，非unformat 未格式化的 undelete 恢复uninstall 卸载 unimportant 不重要的（ 11 ） poly- 多，复，聚polycrystal 多晶体 polytechnical 多工艺的polyatomic 多原子的 polyester 聚脂（ 12 ） -meter 计量仪器barometer 气压表 telemeter 测距仪

·55·23/4/21 计算机专业英语 55

典型的派生词

（ 13 ） -ware 件，部件hardware 硬件 software 软件（ 14 ） -able 可能的programmable 可编程的 portable 便携的adjustable 可调整的 considerable 值得重视的（ 15 ） -lity … 性能reliability 可靠性 confidentiality 保密性（ 16 ） -ize … 化，变成characterize 表示…的特性 industrialize 使工业化optimize 完善 realize 实现

·56·23/4/21 计算机专业英语 56

典型的派生词

（ 17 ） -ment 行为，状态development 发展 agreement 同意，协议equipment 设备 adjustment 调整（ 18 ） -ic 有……特性的，属于……的academic 学术的 elastic 灵活的atomic 原子的 periodic 周期的（ 19 ） -ive 有……性质的，与……有关的productive 生产的 expensive 昂贵的active 主动的 attractive 有吸引力的（ 20 ） -ate 成为……，处理eliminate 消除 circulate 循环，流通terminate 终止 estimate 估计，估算

·57·23/4/21 计算机专业英语 57

借用词

借用词是指借用公共英语及日常生活用语中的词汇来表达专业含义。借用词一般来自厂商名、商标名、产品代号名、发明者名、地名等，也可将普通公共英语词汇演变成专业词意而实现。也有对原来词汇赋予新的意义的。如：cache 高速缓存 semaphore 信号量firewall 防火墙 mailbomb 邮件炸弹fitfall 子程序入口 flag 标志，状态register 寄存器 router 路由器sector 扇区 package 软件包

·58·23/4/21 计算机专业英语 58

转换词（ conversion ）

在英语中，一些单词可以从一种词类转换为另一种词类，转换时词形一般不变，有时发生重音或尾音的变化，转换后的词义往往与原来的词义有密切的联系。如：

名词转化为动词 use 用途 to use 使用 time 时间 to time 计时，定时 format 格式 to format 格式化 program 程序 to program 编程

·59·23/4/21 计算机专业英语 59

转换词（ conversion ）

动词转化为名词 to talk 交谈 talk 谈话，讲话 to test 测验，检查 test 测试，检验 to increase 增加 increase 增加，增量（注意重音不同） 形容词转化为名词 mineral 矿物的 mineral 矿物质 good 好的 good 益处 final 最后的 final 决赛

·60·23/4/21 计算机专业英语 60

词汇缩略

词汇缩略是指将较长的单词取其首部或主干构成与原词同义的短单词，或者将组成词汇短语的各个单词的首字母拼接为一个大写字母的字符串，通常词汇缩略在文章索引、前序、摘要、文摘、电报、说明书、商标等科技文章中频繁采用。

对计算机专业来说，在程序语句、程序注释、软件文档、互联网信息、文件描述中也采用了大量的缩略词汇作为标识符、名称等。

缩略词汇的出现方便了印刷、书写、速记、以及口语交流等，但也同时增加了阅读和理解的困难。

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词汇缩略的形式

节略词（ Clipped words ）。某些词汇在发展过程中为方便起见逐渐用它们的前几个字母来表示，这就是节略词。

如 ： maths——mathematics ， ad——advertisement ， kilo——kilogram ， dir——directory 等。

首字词（ Initials ）。首字词与缩略词基本相同，区别在于首字词必须逐字母念出。 如 ： CAD——Computer Aided Design ， CPU——Central Process

Unit ， DBMS——DataBase Management System （数据库管理系统）， CGA——Color Graphics Adapter （彩色图形适配器）等。

·62·23/4/21 计算机专业英语 62

词汇缩略的形式

缩写词（ Abbreviation ）。缩写词并不一定由某个词组的首字母组成，有些缩写词仅由一个单词变化而来，而且大多数缩写词每个字母后都附有一个句点。

如： e.g. —— for example ， Ltd. —— limited ， sq. —— square 等。 缩略词（ Acronyms ）。是指由某些词组的首字母所组成的新词。 如： ROM——Read Only Memory ， RAM——Random Access Memory ， RISC

——Reduced Instruction Set Computer （ 精 简指令集计 算 机 ） ， CISC——Complex Instruction Set Computer （复杂指令集计算机）， COBOL——Common Business Oriented Language （面向商务的通用语言）等。

·63·23/4/21 计算机专业英语 63

计算机专用术语与命令

在计算机语言、程序语句、程序文本注释、系统调用、命令字、保留字、指令字以及网络操作中广泛使用专业术语进行信息描述。

随着计算机技术的发展，这样的专业术语还会进一步增加。

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专用的软件名称

NextStep 面向对象操作系统（ Next ）Netware 局域网络操作系统（ Novell ）Cairo 面向对象操作系统（ MS ）Daytona 视窗型操作系统（ MS ）Java 网络编程语言（ Sun ）Excel 电子表格软件（ MS ）Delphi 视窗系统开发工具（ Borland ）Informix 关系数据库系统（ Informix ）Navigator 互联网浏览软件（ Netscape ）

·65·23/4/21 计算机专业英语 65

DOS系统

DOS （ Disk Operating System ）是个人计算机磁盘操作系统， DOS 是一组非常重要的程序，它帮助用户建立、管理程序和数据，也管理计算机系统的设备。 DOS 是一种 层 次 结 构 ，包括 DOS BIOS （ 基 本输入输出系统） 、 DOS 核心部分 和 DOS COMMAND （命令处理程序）。

一般情况下，在 DOS启动盘上有配置系统文件 CONFIG.SYS ，在该文件内给出有关系统配置命令，能确定系统的环境。

·66·23/4/21 计算机专业英语 66

配置系统的内容

设置 Ctrl-Break （ BREAK ）检查 格式： BREAK = [ON] | [OFF] 隐含是 BREAK = OFF ，这时 DOS只是对以下过程中检查 Ctrl-Break ： 标准输出操作、标准输入操作、标准打印操作和标准辅助操作。 如果设置 BREAK = ON ，则 DOS 在它被调用的任何时候都检查 Ctrl-Break ，比如编

译程序，即使没有标准设备操作，在编译过程中遇到错，能使编译停止。

·67·23/4/21 计算机专业英语 67

配置系统的内容

指定磁盘缓冲区的数目（ BUFFERS ） 格式： BUFFERS = X ， X 是 1 99之间的数。 指定国家码及日期时间格式（ COUNTRY ） 格式： COUNTRY = XXX ， XXX 是电话系统使用的三数字的国际通用国家码。 建立能由文件控制块打开的文件数（ FCBS ） 格式： FCBS = m ， n m取值 1 255 。 n指定由 FCBS打开但不能由 DOS自动关闭的文件数， n取值 0 255 ，约定值是 0 。

·68·23/4/21 计算机专业英语 68

配置系统的内容

指定能一次打开的最大文件数（ FILES ） 格式： FILES = X X取值 8 255 ，约定值是 8 。 指定能访问的最大驱动器字母（ LASTDRIVE ） 格式： LASTDRIVE = X X可以是 A 到 Z之间的字母，它表示 DOS 能接受的最后一个有效驱动器字母，约定值

为 E 。 指定高层命令处理程序的文件名（ SHELL ） 格式： SHELL = [d ： ] [path] filename [.ext ] [parm1] [parm2]

·69·23/4/21 计算机专业英语 69

配置系统的内容

安装驱动程序（ DEVICE ） 格式： DEVICE = [d ： ] [path] filename [.ext] 除标准设备外，如果用户增加了别的设备，就要由用户自己提供相应的驱动程序。在

CONFIG.SYS 中加上命令 DEVICE = 驱动程序名称。 指定堆栈空间（ STACKS) 格式： STACKS = n ， s n 是堆栈的框架个数， 8 64 s 是每层堆栈框架的字节数， 32 512

·70·23/4/21 计算机专业英语 70

计算机专用命令和指令

系统命令与程序无关，而且语法结构简单。主要的系统命令有系统连接命令、初始化命令、程序调试命令和文件操作命令。即：

系统命令 <CR> 其中 <CR> 为回车换行符，一般而言，系统命令总是立即被执行，但某些系统命令也可以用于程序执行。

每一个处理器都具有很多指令，每一台机器也具有很多系统命令，不同的操作系统也定义了不同的操作命令，它们通常是缩写的，牢记这些指令，就熟悉了计算机的操作；了解缩写的含义，也就了解了所用的操作的含义。

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计算机专用命令和指令

创建目录 MD （ make directory ） 改变目录 CD （ change directory ） 删除目录 RD （ remove directory ） 列表目录 DIR （ directory ） 重命名 REN （ rename ） 中断请求 INT （ call to interrupt procedure ） 中断返回 IRET （ interrupt return ） 取数据段地址指令 LDS （ load doubleword pointer ） 取偏移地址指令 LEA （ load effective address offset ） 串装入操作指令 LODS （ load string operand ） 总线封锁命令 LOCK （ assert bus lock signal ）

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Internet 专用缩写术语

TCP/IP协议： Internet 使用的一组网络协议，其中 IP 是 Internet Protocol ，即网际协议； TCP 是 Transmission Control Protocol ，即传输控制协议，这是最核心的两个协议。 IP协议提供基本的通信， TCP协议提供应用程序所需要的其他功能。

SMTP ：简单邮件传送协议（ Simple Mail Transfer Protocol ），用于电子邮件传送。 FTP ：文件传输协议（ File Transfer Protocol ），用来实现计算机之间的文件拷贝。

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Internet 专用缩写术语

TELNET ：远程登录协议。可以看成是 Internet 的一种特殊通信方式，它的功能是把用户正在使用的终端或主机变成它要在其上登录的某一远程主机的仿真远程终端。

HTTP ：超文本传输协议（ Hypertext Transfer Protocol ），用于 World Wide Web服务。

SNMP ：简单网络管理协议（ Simple Network management Protocol ），用于网络管理。

TFTP ：简单文件传输协议（ Trivial File Transfer Protocol ），用于无盘工作站的自举。

·74·23/4/21 计算机专业英语 74

Internet 专用缩写术语

BOOTP ：自举协议（ Bootstap Protocol ），用于无盘工作站的启动。 NFS ：网络文件系统（ Network File System ），用于实现计算机间共享文件系统。 UDP ：用户数据报协议（ User Datagram Protocol ），用于可靠性要求不高的场合。 ARP ：地址解析协议（ Address Resolution Protocol ），用于从 IP 地址找出对应

的以太网地址。

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Internet 专用缩写术语

RARP ：逆向地址解析协议（ Reverse Address Resolution Protocol ），用于从以太网地址找出对应的 IP 地址。

ICMP ： Internet控制信息协议（ Internet Control Message Protocol ）。 IGMP ： Internet 成组广播协议（ Internet Group Multicast Protocol ）。

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Internet服务

E-mail ：电子邮件，指通过计算机网络收发信息的服务。电子邮件是 Internet 上最普遍的应用，它加强了人与人之间沟通的渠道。

Telnet ：远程登录，用户可以通过专门的 Telnet命令登录到一个远程计算机系统，该系统根据用户帐号判断用户对本系统的使用权限。

FTP （ File Transfer Protocol ）：文件传输协议，利用 FTP服务可以直接将远程系统上任何类型的文件下载到本地计算机上，或将本地文件上载到远程系统。它是实现Internet 上软件共享的基本方式。

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Internet服务

Usenet ：新闻组，又称网上论坛或电子公告板系统（ Bulletin Board System, BBS ），是人们在一起交流思想观点，公布公共注意事项，寻求帮助的地方。

WWW （ World Wide Web ）：万维网，当前 Internet 上最重要的服务方式。 WWW是由欧洲粒子物理研究中心（ CERN ）研制的，它将位于全球 Internet 上不同地点的相关多媒体信息有机地编织在一起，称为 Web页的集合。

·78·23/4/21 计算机专业英语 78

Internet 地址

域名，它是 Internet 中主机地址的一种表示方式。域名采用层次结构，每一层构成一个子域名，子域名之间用点号隔开并且从右到左逐渐具体化。

域名的一般表示形式为：计算机名、网络名、机构名、一级域名。 一级域名有一些规定，用于区分机构和组织的性质。 如： edu 教育机构、 com 商业单位、 mil 军事部门、 gov 政府机关、 org 其它组织。

·79·23/4/21 计算机专业英语 79

区分地域的一级域名

cn 中国 ca 加拿大us 美国 au 澳大利亚gb 英国（官方） uk 英国（通用）tw 中国台湾 hk 中国香港fr 法国 un 联合国nz 新西兰 dk 丹麦ch 瑞士 de 德国jp 日本 sg 新加坡aq 南极洲 it 意大利

·80·23/4/21 计算机专业英语 80

电子邮件（ E-mail ）地址的标准格式

用户名 @ 主机域名。 例如， wang@online.sh.cn 是一个电子邮件的地址，其中 wang 是用户名， @ 是连接符， online.sh.cn 是“上海热线”的主机域名，这是注册“上海热线”后得到的一个E-mail 地址。

·81·23/4/21 计算机专业英语 81

专用计算机厂商及商标名

Microsoft 微软 Philip 飞利浦Compaq 康柏 DELL 德尔Panasonic 松下 ASUS 华硕Samsung 三星 Intel 英特尔Acer 宏基 Epson 爱普生Hewlett-Packard (HP) 惠普IBM

·82·23/4/21 计算机专业英语 82

专业英语中常用的符号和数学表达式

加法（ addition ） 3 + 4 = 7 Three plus four equals seven. 或 Three plus four is seven. 减法（ subtraction ） 7 – 3 = 4 Seven minus three leaves four. 或 Seven minus three equals four. 或

Seven minus three is four.. 乘法（ multiplication ） 3 × 4 = 12 Three multiplied by four is twelve. 除法（ division ） 15 ÷ 3 = 5 Fifteen divided by three is five.

·83·23/4/21 计算机专业英语 83

关系运算符

在等式表达中，常用到等号（ = ），而在一些不等关系表达中，则要用到表示不等关系的各种符号（、、、、、）。下面分别举例说明。a = b a equals b 或 a is equal to b 或 a is ba b a is approximately equal to ba b a is not equal to b 或 a is not ba b a is less than or equal to ba b a is more than or equal to ba b a is less than ba b a is greater than b

·84·23/4/21 计算机专业英语 84

分数

分数词由基数词和序数词搭配而成，分子用基数词，分母用序数词。 当分子是 1 时，可以用“ one” 或“ a” ，分母使用序数词；当分子大于 1 时，分子使

用基数词，而分母要用序数词的复数形式。 分数的另外一种表示方法是将“ /” 说成是“ over” 。对于假分数，也就是分数由一个整数和一个真分数组成，则说成是“整数部分 and 真小数部分”。

·85·23/4/21 计算机专业英语 85

分数举例

1/5 one fifth 或 a fifth

3/4 three fourths 或 three quarters

1/2 a half

45/199 forty-five over one hundred and ninety-ninth

3 又 2/3 three and two thirds

·86·23/4/21 计算机专业英语 86

小数

对于小数的表示，直接将组成小数的各个数字读出。其中小数点可以说成是“ point” 。 0 的表示可以有多种，可以是： zero ， naught ，或 o （字母“ o” 的音）。 0.5 zero point five

0.08 zero point zero eight

302.67 three o two point six seven

·87·23/4/21 计算机专业英语 87

百分数

百分数用 percent 表示，既可与 by连用，也可单独使用。 百分数在句子中主要作状语。 例： Its total output value increased by 10 percent over the previous year.

译文：它的总产值比去年增长了百分之十。例： The output of computers in China last year was 25 percent more than in 2000.

译文：去年中国计算机的产量比 2000年上升了百分之二十五。

·88·23/4/21 计算机专业英语 88

倍数

倍数的表达在计算机专业英语中时常出现，一般用“ times” 表示。而倍数也是“汉译英”及“英译汉”中的难点，稍有不慎，就会产生理解错误。

在简单的倍数表示法中，主要使用“… x times as … as” 、“… x times the size (length, width, height, depth, amount) of …” 和“… x times + 比较级 + than …”几种形式。

例： The speed of this new printer is four times faster than that old one.

译文：这台新打印机的速度比那台旧打印机快四倍。

·89·23/4/21 计算机专业英语 89

倍数

对于增加倍数的表示，在“ increase” 等表示“增加”或“提高”词的后面也可用“ times” 。

若是“ increase by x times” ，则翻译为“增加了 x倍”或“增加到原来的 x+1倍”。

另外，在“ increase by”后面除可用“ x times”外，也可使用其它数词。 “increase”后面也可跟介词“ to” ，表示“增加到……”。 例： Next year the output of computers will increase by four times.

译文：明年计算机的产量将增加到五倍。

·90·23/4/21 计算机专业英语 90

倍数

对于减少倍数的表示，在“ decrease” 或“ reduce” 等表示“减少”或“降低”的词后面也常用“ times” 。

若是“ decrease by x times” ，则常译为“减少到 1/x” 或“减少了 1 减 1/x” 。 “decrease by” 也可使 用其它 数 词 ，“ decrease to” 表 示“减少到……” 。 注

意，“ by”后面表示的是净增减数，“ by” 有时可以省略，而“ to”后面为增加或减少后达到的数字。

例： The new equipment they are designing will reduce error probability by three times and its speed will increase by two times.

译文：他们正在设计的那种新设备将使误差率降低到三分之一，而速度将增加两倍。

·91·23/4/21 计算机专业英语 91

章节、页数的表示法和读法

第一章 the First Chapter 或 Chapter One

第二节 the Second Section 或 Section Two

第三课 the Third Lesson 或 Lesson Three

第 463页 page four six three

第 2564页 page two five six four 或 page twenty-five sixty-four

·92·23/4/21 计算机专业英语 92

1.3 计算机专业文献的阅读与翻译

计算机专业文献的阅读方法 计算机专业文献翻译的基本方法

·93·23/4/21 计算机专业英语 93

计算机专业文献的阅读方法

学习性阅读：这种阅读，用于学习文化知识、参加考试、知识竞赛等。因为要学习文章中的字、词、句、段、篇，还要了解文章的作者、体裁、结构和写作特点等，所以要慢速阅读。

涉猎性阅读：课外活动时，浏览书籍报刊，以求扩大知识面，获得有关信息，所以要快读。

搜索性阅读：为了搜索某些资料所采用的一种阅读。如掌握一本书、一个章节或一篇文章总的观点等，阅读的速度要中等。

·94·23/4/21 计算机专业英语 94

略读

略读是指以尽可能快的速度进行阅读。了解文章的主旨和大意，对文章的结构和内容获得总的概念和印象。进行略读时精力必须特别集中，还要注意文中各细节分布的情况。略读时主要注意以下几点： 注意短文的开头句和结尾句，力求抓住文章的主旨大意。 注意了解文章的主题句及结论句。 注意文章的体裁和写作特点，了解文章结构。 注意支持主题句或中心思想的信息句，其它细节可以不读。

·95·23/4/21 计算机专业英语 95

查读

查读的目的主要是要有目的地去找出文章中某些特定的信息，也就是说，在对文章有所了解的基础上，在文章中查找与某一问题、某一观点或某一单词有关的信息。

查读时，要以很快的速度扫视文章，确定所查询的信息范围，注意所查信息的特点，而与所查信息无关的内容可以略过。

·96·23/4/21 计算机专业英语 96

精读

精读是指仔细地阅读，力求对文章有深层次的理解，以获得具体的信息。 包括理解衬托主题句的细节，根据作者的意图和中心思想进行推论，根据上下文猜测词义等。

对难句、长句，要借助语法知识，对其进行分析，达到准确的理解。

·97·23/4/21 计算机专业英语 97

阅读技能

掌握所读材料的主旨大意。 了解阐述主旨的事实和细节。 根据上下文判断某些词汇和短语的意义。 既理解个别句子的意义，也理解上下文之间的逻辑关系。 根据所读材料进行一定的判断、推理和引申。 领会作者的观点、意图和态度。

·98·23/4/21 计算机专业英语 98

鉴别阅读法

鉴别阅读法是一种快速提炼文章的段意、主要内容和中心思想的阅读方法。鉴别阅读法包括下列三个环节：

划分出文章的段落，迅速找出段落的中心句、重点句，或用自己的语言概括出段意。

连接各段的段意，分析文章的重点句、段，归纳主要内容。 在阅读过程中，要留意文章的题目、开头段、结尾段以及文章的议论部分，从中

概括出中心思想。 鉴别阅读法实际上是通过以上三个环节来掌握文章的重要信息，因而无须一字不漏地通读全文。

·99·23/4/21 计算机专业英语 99

默读法

在阅读时，大脑直接感受文字的意思，不必通过发音器官将文字转换为声音，这种阅读方式就叫无声阅读。

在进行无声阅读时，由于发音器官受抑制，视觉不受逐字换音的牵制，因而视角广度大，便于以句、以行、甚至以段为单位进行阅读，还可以根据阅读目的的需要进行浏览、跳读。

由于是直接理解文字的意义，省掉了发音阶段，所以无声阅读的速度比出声阅读的速度快得多。

·100·23/4/21 计算机专业英语 100

视觉辅助阅读法

很多阅读者常常在阅读时用手指点着单词，传统上把这种习惯看成是一种错误，并要求他们把手指从书本上拿开。

现在看来，要做的不是叫他们把手指从书本上拿开，而是让他们更快地移动手指。 显然，手指不会减缓眼睛的移动，相反，它在帮助养成流畅的阅读节奏方面有着不可估

量的作用。 当然，读者也不必局限于使用手指作为视觉引导物，也可以用钢笔或铅笔引导视觉。

·101·23/4/21 计算机专业英语 101

提高阅读能力的方法

1. 打好语言基本功2. 在阅读实践中提高阅读能力3. 掌握正确的阅读方法4. 利用专业性文章段落结构知识提高阅读速度和理解能力。

·102·23/4/21 计算机专业英语 102

计算机专业文献翻译的基本方法

在科技英语翻译中，准确是第一要素，如果为追求译文的流畅而牺牲准确，不但会造成科技信息的丢失，影响文献交流，还可能引起误解，造成严重后果。

由于准技术词汇的扩展意义（即技术意义）在科技文献中出现的频率要比其一般意义大得多。因此对这种词的翻译应充分考虑其技术语境。

有些语境提供的暗示并不充分，这要靠译者从更广阔的篇章语境中去寻找合理的解释，给出合适的翻译。

·103·23/4/21 计算机专业英语 103

专业英语翻译的基本方法

要作好翻译工作，必须从深刻理解原文入手，力求做到确切表达译文。 原文是翻译的出发点和唯一依据，只有彻底理解原文含义，才有可能完成确切的翻译，才能达到上述翻译标准的要求，要深刻理解原文，首先要认识到专业科技文献所特有的逻辑性、正确性、精密性和专业性等特点，力求从原文所包含的专业技术内容方面去加以理解。

其次，要根据原文的句子结构，弄清每句话的语法关系，采用分组归类的方法辨明主语、谓语、宾语及各种修饰语，联系上下文来分析和理解句与句之间、主句与从句之间的关系。

·104·23/4/21 计算机专业英语 104

科技文献翻译中的汉语表达切忌以下几点：

1. 不符合汉语逻辑。2. 过于强调“忠实”使原文与译文貌合神离。3. 中文修辞不当，表达中存在明显的翻译腔。4. 表达罗嗦、不简洁。

·105·23/4/21 计算机专业英语 105

词义的选择与引伸

词义的选择：在翻译过程中，若英汉双方都是相互对应的单义词时则汉译不成问题，如ferroalloy （铁合金）。然而，由于英语词汇来源复杂，一词多义和一词多性的现象十分普遍，比如 power 在数学中译为“乘方”，在光学中译为“率”，在力学中译为“能力”，在电学中译为“电力”。

词义的引伸：英汉两种语言在表达方式方法上差异较大，英语一词多义现象使得在汉语中很难找到绝对相同的词。如果仅按词典意义原样照搬，逐字硬译，不仅使译文生硬晦涩，而且会此不达意，造成误解。因此，有必要结合语言环境透过外延看内涵，把词义做一定程度的扩展、引伸。

·106·23/4/21 计算机专业英语 106

词语的增减与变序

由于英语和汉语各自独立演变发展，因而在表达方法和语法结构上有很大的差别。在英译汉时，不可能要求二者在词的数量上绝对相等。通常应该依据句子的意义和结构适当增加、减少或重复一些词，以使译文符合汉语习惯。

英语中各种短语或定语从句作修饰语时，一般都是后置的，而汉语的修饰语几乎都是前置的，因而在翻译时应改变动词的顺序。

·107·23/4/21 计算机专业英语 107

词性的转换

可转换成汉语动词的情况：名词、名词化结构以及起名词作用的不定式、动名词等一般均可译成汉语的动词；英语介词在构成状语、含有动词意义时都可以翻译成汉语的动词；作表语的形容词和副词可以转换成汉语的动词来翻译。

可转换成汉语名词的情况：有些英语动词表达的概念难以直接用汉语的动词来翻译时，可以采取转换为汉语名词的方法。

可转换成汉语形容词的情况：修饰动词的副词，由于动词转换成汉语的名词，所以可以相应地将副词转换成形容词；修饰形容词的副词，由于形容词转换成汉语名词，所以可以相应地将其转换为汉语形容词；副词作定语修饰名词时，可以翻译成汉语形容词。

可转换成汉语副词的情况：修饰名词的形容词，当名词转换成汉语动词时，应当将其转换成汉语副词。

·108·23/4/21 计算机专业英语 108

语法成分的转换

为了使译文达到“明确”、“通顺”和“简练”的要求，有时需要把原语句中的某种成分转译为另一种成分。

成分的转换在大多数情况下并不引起词性的转换，而词性的转换经常会引起成分的转换。

·109·23/4/21 计算机专业英语 109

主语的转译

为了使译文简明通顺，要把英语的被动句译成汉语的主动句，这时常常把英语句中的主语转译为汉语的宾语。有时根据译文修辞上的需要，将英语主动句的主语转译为汉语的宾语。这种转译中的词性一般不变。

汉语句中的主语有时可转换成英语的宾语、介词宾语、表语、谓语、状语或定语。

·110·23/4/21 计算机专业英语 110

谓语的转译

为了使译文符合汉语习惯，把英语句中的谓语动词转译为汉语名词并将它作为主语。有时为了使译文更简明通顺，也将英语句中的谓语转译成汉语句的宾语、定语、状语等成分。

汉语句中的谓语有时可转译成英语的定语、状语、补语、宾语、主语或表语。

·111·23/4/21 计算机专业英语 111

宾语的转译

当英语句中的动词宾语或介词宾语在意义上与主语有密切联系时，可以将这种英语句中的宾语转译成汉语句的主语。另外当英语名词转译为汉语动词或形容词时，可能发生宾语转译成谓语的情况。

汉语中常常使用无主句，或在一定的上下文中将主语省略。这样的句子译成英语时，句中的宾语就变成英语被动语态句式的主语。有时汉语句中的宾语还可以转译成英语的状语、定语或表语。

·112·23/4/21 计算机专业英语 112

定语的转译

英语中常常利用定语来表达事物的性质、特点和参数，而汉语却无此习惯。因此，遇到这种情况时，可将英语句中的定语转译成汉语的表语。另外充当名词定语的形容词转译为动词时，经常发生定语转译为谓语的情况。充当定语的分词、分词短语或介词短语也可转译为谓语。

汉语句的定语一般放在它所修饰的词语之前，而英语则可前可后，有时汉语定语较长，如不变为英语后置定语，还可译为状语。此外，汉语中的定语有时还可以转译为英语的谓语、宾语或主语。

·113·23/4/21 计算机专业英语 113

状语的转译

当英语句中的副词转译为汉语句中的名词时，经常发生状语转译为主语的情况。充当状语修饰谓语动词的介词短语，有时也可以转译为汉语译句的主语。另外，有时根据修辞的需要，把英语句中用作状语的副词转译为汉语译句的补语、定语、谓语、表语或宾语等。

汉语句中的状语有时可转译为英语句的表语、定语、谓语或主语。

·114·23/4/21 计算机专业英语 114

翻译科技资料时要注意的问题

首先要把原文全部阅读一遍，了解其内容大意，专业范围和体裁风格，然后开始翻译。 遇到生词，不要马上查字典，应该先判断是属于普通用语，还是属于专业用语。 翻译时，最好不要看一句译一句，更不能看一个词译一个词。而应该看一小段，译一小段。这样做便于从上下文联系中辨别词义，也便于注意句与句之间的衔接，段与段之间的联系。

翻译科技文献时要求译文必须概念清楚，逻辑正确，数据无误，文字简练，语句流畅。

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专业术语的翻译

意译 音译 象译 形译 计算机专业的新技术词汇不断出现。 这些词往往通过复合构词（ compounding ）或缩略表达全新的概念。 它们由于在词典中缺乏现成的词项，一个词往往会有两个甚至两个以上的译名，造成很

大混乱。 全国科学技术名词审定委员会为了规范译名，定期发表推荐译名，因此我们还必须跟踪

计算机行业的发展，掌握新出现的词汇。

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意译

科技术语在可能情况下应尽量采用意译法。采用这种方法便于读者顾名思义，不加说明就能直接理解新术语的确切含义。例：loudspeaker 扬声器 semiconductor 半导体 modem = modulator + demodulator 调制解调器 copytron = copy + electron 电子复写（技术）

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音译

当由于某些原因不便采用意译法时，可采用音译法或部分音译法。 例： Radar 是取 radio detection and ranging 等词的部分字母拼成的，如译成“无线电探测距离设备”，显得十分罗嗦，故采用音译法，译成“雷达”。又如： bit 比特（二进制信息单位） baud 波特（发报速率单位） quark 夸克（基本粒子，属新材料类） nylon 尼龙（新材料类）

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象译

英文用字母或词描述某种事物的外形，汉译时也可以通过具体形象来表达原义，称之为“象译”。例：I-shaped 工字形Y-connection Y 形连接Zigzag wave 锯齿形

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形译

科技文献常涉及到型号、牌号、商标名称及代表某种概念的字母。这些一般不必译出，直接抄下即可，称为“形译”。例：Q band

Q波段（指 8毫米波段，频率为 3646千兆赫）p-n-p junction

p-n-p 结（指空穴导电型—电子导电型—空穴导电型的结）

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屏幕显示信息的翻译

目前大部分软件都采用了菜单技术及其它人机对话技术。能否正确地阅读和理解这些屏幕信息，关系到我们能否正确使用这些软件以及充分发挥软件所提供的全部功能。

屏幕首先显示出提供的功能名称，用户根据需要指出希望完成的功能，然后由程序分析用户的选择并调用不同的功能块进行处理。

一个软件能否为用户所欢迎，在很大程度上取决于它的人机交互性能。

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设计屏幕信息时应遵守的原则

1. 检测所有输入数据的合法性。2. 输入方式要简单，并尽可能每一步给出屏幕提示。3. 如果用户选择的功能可能会产生严重的后果（如删除文件、格式化磁盘等），应再

次予以确认，以提醒用户不致误操作。4. 尽量减少用户处理出错的工作量。5. 屏幕显示信息应简洁、易懂，避免二义性。6. 尽可能在一屏中包含更多的信息。

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常见的屏幕输出信息的语法特点

1. 引导用户按一定步骤进行某些操作。这种类型通常使用祈使语句。2. 要求用户回答某一个问题。所用句型通常是 Yes/No 型疑问句，也有按填空的方式

向用户提出要求的。3. 报告错误信息或其他提示信息。既可以用短语表示，也可以用一些简单句来表示。

为了醒目，有时还配上一些特殊标记（如 * * * 等）。4. 程序调试过程中的出错信息。

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翻译的过程

理解原文是确切表达的前提。译者首先应该结合上下文，通过对词义的选择，语法的分析，彻底弄清楚原文的内容和逻辑关系。

表达就是要寻找和选择恰当的语言材料，把已经理解了的原作内容重新叙述出来。 校对阶段，是理解和表达的进一步深化，是使译文符合标准的一个必不可少阶段，是

对原文内容的进一步核实，对译文语言的进一步推敲。

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科技翻译需要熟悉和掌握如下的知识

掌握一定的词汇量 具备科技知识，熟悉所翻译专业 了解中西方文化背景的异同，科技英语中词汇的特殊含义 日常语言和文本的表达方式以及科技英语翻译技巧

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翻译要在保持原意的基础上灵活引申

(1) 通读整个句子，了解初步含义。重点注意谓语动词、连词、介词、专用词组和实义动词以及暂时不了解的新词汇。

(2) 决定是否分译，如何断句。原句标点和句型结构如何，语态及时态如何，灵活组织，保持前后文之间的逻辑联系和呼应关系。

(3) 决定汉语如何表达，如何组句，所选汉语词意是否确切。译文是否要进行查、加、减、改或者引申译法。概念明确、用词恰当、逻辑清楚、文字通顺。

(4) 翻译完成后要多读译文，是否通顺、能懂、上下文及逻辑关系对不对等，即要译者自己懂，也要尽量使别人阅读译文后也能懂，要为读者着想。

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Computer Basics

Definition of computer: A computer is an electronic devie that can receive a set of instructions, or

program, and then carry out this program by performing calculations on numerical data or by manupilating other forms of information.

A computer is a fast and accurate symbol manipulating system that is organized to accept, store, and process data and produce output results under the diretion of a stored program of instructions.

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Computer Basics

History precursor: adding machine, 1642, Freach scientist Blaise Pascal, using a series of

ten-toothed wheels pioneers: analytical engine, 19th, British scientist Charles Babbage, having input

stream, store, mill, printer Anologue computers, late 19th, British physist Lord Kelvin, using shafts and gears Electronic computers:

a. colossus(all-electronic digital computers), including 1500 vacuum tubes

b. ENIAC(prototype), including 18000 vacuum tubes

c. transister

d. integrated circuits: LSI & VLSI Future developments (microminiaturization)

Artificial intelligence Neural network Optical computers

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Computer Basics

Computer generations

If we take the development of electronic component as the criterion of dividing computer generations, there are the following four computer generations:

The first generation of computers (1946-1959)

It is characterized by the vacuum tube The second generation of computers (1959-1964)

It is characterized by the transistors The third generation of computers (1964-1971)

It is characterized by the integrated circuit The fourth generation of computers (1971-)

It is characterized by the large-scale integration Some people say that we are in the fifth generation of computers. Most

commentators think that even though technological innovations are coming in rapid succession, no single innovation is, or wil be, significant enough to characterize another generation of computers.

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Computer Basics

Types of computers

1. If we take the purpose of a computer system into consideration, we can put the computer system into two categories:

The special purpose computer system: is desiged to perform only one specific task. It lacks versatility.

The general-purpose computer system: it can store different programs and can thus be used in countless applications.

2. If we consider the size, cost, performance factor of a computer system, we can classify the computer system into the following five categories:

Microcomputers: the smallest general-purpose system, such as laptops, palmtops Workstations: a microcomputer with enhanced graphics and communications capabilities for

office work

.

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Computer Basics

Minicomputers: also small general-purpose system, typically more powerful and expensive than micros. Too expensive for personal use, suited to a business, school or laboratory.

Mainframe computers: much larger system, offering faster processing speeds and greater storage capacity than a typical mini. Often used by major business enterprises, government departments, scientific research establishment

Super-computers: the largest and the fastest system, designed to process complex scientific applications.

Generally speaking, as the size of a computer increases, the function of the system becomes more powerful, the processing speed becomes faster, and the storage capacity and cost becomes much greater.

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第 2 章 Hardware Knowledge

Guiding Questions:

1. A computer system includes two parts, what they are?

2. How many parts does computer hardware include? And what are these parts?

3. Show some common input devices.

4. Show some common output devices.

5. How many parts does CPU include, and what they are?

6. Show some common storage devices.

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第 2 章 Hardware Knowledge

The organization of computer hardware input hardware central processing unit output hardware storage hardware bus

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第 2 章 Hardware Knowledge

2.1 Computer Hardware Basics

2.2 CPU

2.3 Memory

2.4 Input / Output Devices

2.5 Parallel Organization

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2.1 Computer Hardware Basics

Flip-Flop and Clock Shift registers Combinational Circuit Logic Systems Logic Circuits

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Flip-Flop and Clock

Microprocessors employ both latches and flip-flops. A flip-flop is a synchronous device; it is clocked, and it can change state only

on arrival of a clock pulse. Clock pulses are basically square waves; they may have a very low repetition,

or they may have a very high repetition rate.

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RS flip-flop

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Shift registers

A register capable of shifting its binary information in one or both directions is called a shift register.

All flip-flops receive common clock pulses that initiate the shift from one stage to the next.

A register capable of shifting in one direction only is called a unidirectional shift register. A register that can shift in both directions is called a bi-directional shift register.

Some shift registers provide the necessary input terminals for parallel transfer.

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4-bit shift register

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The capabilities of register

An input for clock pulses to synchronize all operations. A shift-right operation and a serial input line associated with the shift-right. A shift-left operation and a serial input line associated with the shift-left. A parallel load operation and n input lines associated with the parallel transfer. N parallel output lines. A control state that leaves the information in the register unchanged even

though clock pulses are applied continuously.

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Combinational Circuit

A combinational circuit is a connected arrangement of logic gates with a set of inputs and outputs. At any given time, the binary values of the outputs are a function of the binary combination of the inputs.

A combinational circuit can be described by a truth table showing the binary relationship between the n input variables and the m output variables.

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Block diagram of a combinational circuit

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Logic Systems

In a DC, or level-logic, system a bit is implemented as one of two voltage levels. If the more positive voltage is the 1 level and the other is the 0 level, the system is said to employ DC positive logic.

The digital levels are not specified precisely, but each state is defined by a voltage range about a designated level, such as 4V1V and 0.2V0.2V.

In a dynamic, or pulse-logic, system a bit is recognized by the presence or absence of a pulse.

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Logic Circuits

The key part of the computer’s internal operations is done in the form known to us as the information processing, and it is realized by means of the logic circuits that have been integrated within various functional units of our computer.

That our point should be made clear is that all the integrated circuits physical elements within our computer can have only either one of the two states: “ On” or “Off”.

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Logic Circuits

Logic, on organized method of reasoning, is used in decision making. To make logic decision with our computer, therefore, we have developed three basic logic circuits(called gates): the OR circuit, the AND circuit, and the NOT circuit.

·145·23/4/21 计算机专业英语 145

Logic Circuits

The design of digital computers is based on a logical methodology called Boolean Algebra which uses three basic operations: logical addition, called the OR function; logical multiplication, called the AND function; and logical complementation, called the NOT function.

The variables in Boolean algebra are binary, namely, the resulting variable of an operation or a set of operations can have only one of the two values: One or Zero. These two values may also be interpreted as being True or False, Yes or No, and Positive or Negative.

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Logic Circuits

A switch is ideally suited to represent the value of any two-state variable because it can only be “off” or “on”.

There are only three basic logic operations: the conjunction(logical product) commonly called AND; the disjunction(logic sum) commonly called OR; and the negation commonly called NOT.

So far,it can be seen that different combinations of switches(the simplest electronic element) may be used to construct our computer’s basic logic circuits.

·147·23/4/21 计算机专业英语 147

Logic Circuits

The OR circuit has two or more inputs and a single output. The inputs and the output can each be at one of two states, 0 or 1. The OR circuit is arranged so that the output is in state 1 when any one of the inputs is in state 1. We can list the various combinations of switch states and the resulting output states. This list is known as a truth table, from which it can be seen that all switches must be open(0 state) for the output 0 state.

This type of circuits is called an OR gate. It is used to make the logic decision on whether or not at least one of several inputs is in the 1 state.

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Logic Circuits

The AND circuit also has several inputs and only one output. However, the circuit output is at a logical 1 state only if all inputs are in the logical 1 state simultaneously.

The AND gate makes the logic decision on whether or not several inputs are all in the 1 state at te same time.

The number of inputs to a gate is called the fan-in. There is only one output signal from a gate, but it may be required that this signal should be fed to several other logic gates. The number of subsequent gates that the output of a particular gate can drive is called the fan-out.

·149·23/4/21 计算机专业英语 149

Logic Circuits

The NOT circuit has a single input and a single output. It is arranged so that the output state is always opposite to the input state. The operation of making the output state opposite to that of the input is called inversion, and a circuit designed to do this is known as an inverter.

Obviously, an inverter has one input and one output while a gate has at least two inputs and one output.

As we have just mentioned above, there are only three basic logic operations and we can have these three logic operations performed by the corresponding logic circuits. All functions within a computer can be performed by combinations of these three basic logic operators.

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Key Words

arbitrary 任意的arrangement 排列，整理asynchronous 异步的bi-directional 双向的Boolean function 布尔函数cascade 级连的，串级combinational circuit 组合电路complement 补充，补足configuration 配置，结构flip-flop 触发器inasmuch 因……之故

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Key Words

inhibit 禁止，抑制initiate 开始，激发interconnection 互联网络microprocessor 微处理器negative-logic 负逻辑parallel transfer 并行传送serial 顺序的，串行的significance 重要性，意义square-wave 方波unidirectional 单向的

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Notes

[1] The logical configuration of a shift register consists of a chain of flip-flops in cascade, with the output of one flip-flop connected to the input of the next flip-flop.

此句中的“ with the output of one flip-flop connected to the input of the next flip-flop” 是独立结构作状语，说明触发器连接的方式。译文：移位寄存器的逻辑结构是由一连串串接的触发器所组成的，一个触发器的输出端连接到相邻的触发器的输入端。

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Notes

[2] Sometimes it is necessary to control the shift so that it occurs with certain clock pulses but not with others.

此句中的“ it” 是形式主语，“ to control the shift” 是真正主语， so that引导状语从句。译文：有时候有必要对移位进行控制以便移位只对某些特定脉冲而不对其他脉冲发生。[3] A register that can shift in both directions is called a bi-directional shift register.

本句用被动语态表示客观性，“ that can shift in both directions” 是主语从句，修饰“ a register” 。译文：能够在两个方向上移位的寄存器叫做双向移位寄存器。

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Notes

[4] A combinational circuit transforms binary information from the given input data to the required output data.

本 句 的 介 词 短 语“ from … to …” 作宾语补足语 ， 进 一步说 明宾语“ binary information” 。译文：组合电路通过传输二进制信息，使得给定的输入数据产生了所需要的输出数据。[5] A combinational circuit can also be specified with m Boolean functions, one for each output variable.

本句的“ one for each output variable” 是同位语。译文：组合电路也能规定m种布尔函数，每种函数对应一个输出变量。

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词组翻译练习

(1)  锁存器 latch

(2)  逻辑电路 logic circuit

(3)  R-S触发器 R-S flip-flop

(4)  有效数据 valid data

(5)  向左移位操作 a shift-left operation

(6)  输出变量 output variable

(7)  8位移位寄存器 8-bit shift register

(8)  二进制信息 binary information

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Reading material ： Digital Computer System

The four basic units of simplified computer: the input unit, central processing unit, memory unit, and output unit.

The central processing unit (CPU) is the heart of the computer system. It is responsible for performing all arithmetic operations and logic decisions initiated by the program.

The memory unit of the computer is used to store information such as numbers, names, and addresses.

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Reading material ： Digital Computer System

In computer system, memory is divided into two different sections, known as main storage and auxiliary storage. They are also sometimes called internal memory and external memory respectively.

The input and output units are the means by which the CPU communicates with the outside world.

The input unit is used to input information and commands to the CPU for processing.

After processing, the information that results must be output. This output of data from the system is performed under control of the output unit.

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A Digital Computer

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2.2 CPU

The purpose of CPU is to retrieve, interpret and direct the execution of software instructions that are provided to the computer.

The CPU means the Central Processing Unit. It is the heart of a computer system.

A CPU can be a single microprocessor chip, a set of chips, or a box of boards of transistors, chips, wires, and connectors.

Differences in CPUs distinguish mainframes, mini- and microcomputers. A processor is composed of two functional units: a control unit and an

arithmetic / logic unit, and a set of special workspaces called registers.

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Most computers have three basic capabilities

Computers have circuits for performing arithmetic operations, such as: addition, subtraction, division, multiplication and exponentiation.

Computers have a means of communicating with the user. Computers have circuits which can make decisions.

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The control unit

The control unit is the functional unit that is responsible for supervising the operation of the entire computer system.

The control unit fetches instructions from memory and determines their type or decodes them.

It then breaks each instruction into a series of simple small steps or actions. By doing this, it controls the step-by-step operation of the entire computer

system.

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The Arithmetic / Logic Unit

Data are brought into the ALU by the control unit, and the ALU performs whatever arithmetic or logic operations are required to help carry out the instructions.

Arithmetic operations include adding, subtracting, multiplying, and dividing. Logic operations make a comparison and take action based on the results.

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Registers

Registers in the control unit are used to keep track of the overall status of the program that is running.

Control unit registers store information such as the current instruction, the location of the next instruction to be executed, and the operands of the instruction.

In the ALU, registers store data items that are added, subtracted, multiplied, divided, and compared.

Other registers store the results of arithmetic and logic operations.

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Instruction

An instruction is made up of operations that specify the function to be performed and operands that represent the data to be operated on.

The processor’s job is to retrieve instructions and operands from memory and to perform each operation. Having done that, it signals memory to send it the next instruction.

This sequence of steps is frequently referred to as the fetch-decode-execute cycle.

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Key Words

analogous 类似的，相似的Arithmetic / Logic Unit 算术逻辑单元awesome 惊人的，令人敬畏的capability 性能，能力chip 芯片decode 解码，译码exponentiation 幂运算fetch 获取，取得instantaneously 瞬间地，即时地microelectronic techniques 微电子技术

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Key Words

operand 操作数originality 创意，创造力overall 全部的register 寄存器remarkable 显著的，不平常的retrieve 恢复switchboard 接线总机transistor 晶体管

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Notes

[1]   The program, which tells the computers what to do and the data, which provide the information needed to solve the problem, are kept inside the computer in a place called memory.

这里的主语是“ the program and the data” ，由 which引导的两个定语从句分别修饰the program 和 the data 。译文：程序的作用是指示计算机如何工作，而数据则是为解决问题提供的所需要的信息，两者都存储在存储器里。[2]   The Arithmetic / Logic Unit (ALU) is the functional unit that provides the computer with logical and computational capabilities.

本句由“ that”引导定语从句，修饰“ the functional unit” 。译文：算术逻辑单元（ ALU ）是为计算机提供逻辑及计算能力的功能部件。

·168·23/4/21 计算机专业英语 168

Notes

[3]   For example, if an instruction is to perform the operation of adding two numbers, it must know what the two numbers are and where the two numbers are. 这里的“ what the two numbers are and where the two numbers are”作宾语，它由两个并列的从句组成。译文：例如，一条指令要完成两数相加的操作，它就必须知道：这两个数是什么？这两个数在哪儿？[4]   A timer called a clock releases precisely timed electrical signals that provide a regular pulse for the processor’s work.本 句 中 的“ that provide a regular pulse for the processor’s work” 修饰 electrical signals 。译文：一个称作时钟的计时器准确地发出定时电信号，该信号为处理器工作提供有规律的脉冲信号。

·169·23/4/21 计算机专业英语 169

词组翻译练习

(1)  智能 intelligence

(2)  取指—译码—执行 fetch-decode-execute

(3)  算术逻辑运算 Arithmetic Logical Operations

(4)  硅 silicon

(5)  区别，辨别 distinguish

(6)  顺序 sequence

(7)  发出，释放 release

(8)  兆赫 Megahertz

·170·23/4/21 计算机专业英语 170

Reading Material ： Microprocessor

Microcomputer, or micro for short, is a kind of computers. It was born in the early 1970s.

The central processor of the micro, called the microprocessor, is built as a single semiconductor device; that is, the thousands of individual circuit elements necessary to perform all the logical and arithmetic functions of a computer are manufactured as a single chip.

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2.3 Memory

A memory cell is a circuit, or in some cases just a single device, that can store a bit of information.

A systematic arrangement of memory cells constitutes a memory. Two basic types of semiconductor memory are random access memory

(RAM) and read-only memory (ROM).

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RAM and ROM

Implicit in the definition of the RAM is that both the read and the write operations are permissible in each cell with also approximately the same access time.

The set of data in ROM is generally considered to be fixed, although in some designs the data can be altered.

A ROM may be used, for example, to store the instructions of a system operating program.

RAM: volatile

ROM: non-volatile

·173·23/4/21 计算机专业英语 173

SRAM and DRAM

Two type of RAM are the static RAM (SRAM) and dynamic RAM (DRAM). The difference is the life time of the data being hold. Data stored on SRAM

have long life time as long as the power is supplied, while those on DRAM have an extremely short life time even though the power is supplied, often about 4 milliseconds. It needs constant refreshing.

A static RAM consists of a basic bi-stable flip-flop circuit that needs only a dc current or voltage applied to retain its memory.

A dynamic RAM is an MOS memory that stores one bit of information as charge on a capacitor. Since the charge on the capacitor decays with a finite time constant (milliseconds), a periodic refresh is needed to restore the charge so that the dynamic RAM does not lose its memory.

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SRAM and DRAM

The advantage of the SRAM is that this circuit does not need the additional complexity of a refresh cycle and refresh circuitry, but the disadvantage is that this circuit is fairly large.

In general, a SRAM requires six transistors. The advantage of a DRAM is that it consists only one transistor and one

capacitor, but the disadvantage is the required refresh circuitry and refresh cycles.

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The general types of ROM

The first is programmed either by the manufacturer (mask programmable) or by the user (programmable, or PROM).

Once the ROM has been programmed by either method, the data in the memory are fixed and cannot be altered.

The second type of ROM may be referred to as an alterable ROM in that the data in the ROM may be reprogrammed if desired.

This type of ROM may be called an EPROM (erasable programmable ROM), EEPROM (electrically erasable PROM), or flash memory(high density, low cost, fast access speed, great storage capacity).

Hybrid type: NV-RAM

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Basic memory architecture

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Memory addresses

Computers that use the binary number system also express memory addresses as binary numbers.

If an address has m bits, the maximum number of cells directly addressable is 2 m.

The significance of the cell is that it is the smallest addressable unit. In recent years, most computer manufactures have standardized on an 8-bit cell, which is called a byte.

Bytes are grouped into words.

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The 80x86 processors

The 80x86 processors, operating in real mode, have physical address-ability to 1 megabyte of memory.

EMS was developed to allow real mode processing to have access to additional memory.

It uses a technique called paging, or bank switching. The requirements for expanded memory include additional hardware and a

software device driver.

·179·23/4/21 计算机专业英语 179

Key Words

adjacent 邻近的，接近的allocate 分配，分派approximately 大约，大致，近于consecutive 连续的，连贯的constitute 构成，组成erasable 可擦除的essential 必要的，基本的etch 蚀刻

·180·23/4/21 计算机专业英语 180

Key Words

hexadecimal 十六进制的implicit 暗示的，绝对的kilobyte 千字节manipulate 操作megabyte 兆字节non-metallic 非金属的octal 八进制的property 适当地，相当地

·181·23/4/21 计算机专业英语 181

Key Words

redirect 更改地址refer to 指，提到，参照refresh 刷新semiconductor 半导体turn off 关闭virtually 事实上volatile 易失的

·182·23/4/21 计算机专业英语 182

Notes

[1]      The number of bits in the address is related to the maximum number of directly addressable cells in the memory and is independent of the number of bits per cell.本句中， of directly addressable cells in the memory修饰 the maximum number 。译文：地址的位数与存储器可直接寻址的最大单元数量有关，而与每个单元的位数无关。[2]      Thus a 16-bit words, whereas a 32-bit machine will have 32-bit registers and instructions for moving, adding, subtracting, and otherwise manipulating 32-bit words.Thus a 16-bit words 是一个省略句，这里的 whereas作“而”讲。译文：因而 16位机器具有 16位的寄存器和指令以实现 16位字的操作； 32位机器则有32位的寄存器和指令，以实现传送、加法、减法和其它他 32位字的操作。

·183·23/4/21 计算机专业英语 183

Notes

[3]      This was the ability to etch thousands of integrated circuits onto a tiny piece (chip) of silicon, which is a non-metallic element with semiconductor characteristics.

由 which引导的是非限定性定语从句，用来修饰 silicon 。译文：这就是将成千上万个集成电路蚀刻在一小块硅（芯）片上的能力。硅片是具有半导体特性的非金属元件。[4]      When a program allocates expanded memory pages, the EMM returns a handle to the requesting program.

本句中，由 when引导了一个时间状语从句。译文：当一个程序装入扩展存储器页中时， EMM 就将一个标志回复给这个请求程序。

·184·23/4/21 计算机专业英语 184

词组翻译练习

(1)  扩展存储器 expanded memory

(2)  半导体存储器 semiconductor memory

(3)  外围电路 peripheral circuit

(4)  实模式 the real mode

(5)  寻址能力 address ability

(6)  组织 organization

(7)  只读存储器 Read Only Memory

(8)  随机存取存储器 Random Access Memory

·185·23/4/21 计算机专业英语 185

Reading material :Magnetic Disks and Optical Disks

There are two major types of magnetic disks: floppy disks and hard disks. Both types of disks rely on a rotating platter coated with a magnetic surface

and use a moveable read/write head to access the disk. Every user has used hard disks and liked them very much since they have

gigantic storage capacity and work fast, especially since operating systems grow larger and larger.

·186·23/4/21 计算机专业英语 186

Reading material :Magnetic Disks and Optical Disks

An optical disk is a disk on which data are encoded for retrieval by a laser. Optical disks offer information densities far beyond the range of current

magnetic mass-storage devices. Read-only optical disks cannot be written on and so have the functional

equivalence of read-only memory （ ROM ） . The most popular version of read-only optical disks employs the same

technology as the CD that has become popular for audio recording.

·187·23/4/21 计算机专业英语 187

Reading material :Magnetic Disks and Optical Disks

Write-once optical disks （ also called write-once, read-mostly, or WORM ） are blank disks that are recorded on by the user.

Erasable optical disks use lasers to read and write information to and from the disk but also use a magnetic material on the surface of the disk and a magnetic write head to achieve erasability.

·188·23/4/21 计算机专业英语 188

2.4 Input / Output Devices

Input is a process that involves the use of a device to encode or transform data into digital codes that the computer can process.

Input devices enable you to input data and commands into the computer. The most common input device is a keyboard. Additional input devices include

the mouse, input pen, scanner, touch screen and microphone. They are all components for interpretation and communication between people and computers.

Input is a process that involves the use of a device to encode or transform data into digital codes that the computer can process. For example, if you press the letter A on the keyboard of a terminal or personal computer, you activate an information processing cycle. The key is simply a switch that senses a finger touch and triggers a cycle to accomplish the following: (1) the keystroke is encoded, or converted into a machine-readable code, (2) the encoded piece of data is stored in a memory location for later processing, and (3) output is provided by displaying the letter A on the computer’s monitor screen.

·189·23/4/21 计算机专业英语 189

2.4 Input / Output Devices

The purpose of output hardware is to provide the user with the means to view information provided by the computr system. That is, what a computer program produces is a stream of coded symbols. In most cases, it is the job of the output device to decode these coded symbols into a form of information that is easy for people to use or understand, such as text, pictures, graphics, or sound.

Common output devices are monitors and printers. Information is output in either hardcopy or softcopy form. Hardcopy output can

be held in your hand---examples are papers with text(words or numbers) or graphics printd on it. Softcopy output is displayed on a monitor, a television-like screen on which you can read text and graphics.

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Keyboard The keyboard is one of the main input devices for computer system. It is the way you will most commonly communicate with a computer. The computer keyboard is much like the keyboard of a typewriter. The computer keyboard has some additional keys called modifier keys. These

are the Shift, Ctrl (control) and Alt (alternate) keys.

·191·23/4/21 计算机专业英语 191

Mouse

A mouse is a small device that a computer user pushes across a desk surface in order to point to a place on a display screen and to select one or more actions to take from that position.

A mouse consists of a metal or plastic housing or casing, a ball that sticks out of the bottom of the casing and rolls on a flat surface, one or more buttons on the top of the casing, and a cable that connects the mouse to the computer.

·192·23/4/21 计算机专业英语 192

Mouse

The most conventional kind of mouse has two buttons on the top: the left one is used most frequently.

The second button, on the right, usually provides some less-frequently needed capability.

For example, when viewing a Web page, you can click on an image to get a pop-up mean that, among other things, lets you save the image on your hard disk.

·193·23/4/21 计算机专业英语 193

Monitor

Monitors maybe are one of the most important output devices. Computers only use monitors to show you exciting operation results or marvelous and vivid pictures.

A character-based display divided the screen into a grid of rectangles, each of which can display a single character.

A bitmap display divides the screen into a matrix of tiny, square “dots” called pixels. Any characters or graphics that the computer displays on the screen must be constructed of dot patterns within the screen matrix.

·194·23/4/21 计算机专业英语 194

Monitor

Resolution refers to the number of individual dots of color, known as pixels, contained on a display.

Dot pitch is the measure of how much space there is between a display’s pixels.

In monitors based on CRT technology, the refresh rate is the number of times that the image on the display is drawn each second.

The scan style of a electron gun in a tube is divided into two styles: interlace and non-interlace.

·195·23/4/21 计算机专业英语 195

Scanner

A scanner is a device that can read text or illustrations printed on paper and translate the information into a form the computer can use.

A scanner works by digitizing an image, dividing it into a grid of boxes and representing each box with either a zero or a one, depending on whether the box is filled in.

Optical scanners do not distinguish text from illustrations; they represent all images as bit maps.

·196·23/4/21 计算机专业英语 196

Key Words

alphabetic 字母的apparently 清楚地，显然地bit map 位图capital letter 大写字母cursor 光标digitize 数字化electron-beam 电子束flicker 闪耀，闪烁illustration 例证，插图integral 整体，整数layout 布局manufacture 制造

·197·23/4/21 计算机专业英语 197

Key Words

matrix 矩阵，阵列non-interlace 非隔行pixel 像素rectangle 矩形replacement 更换，代替resolution 分辨率retinal 视网膜的scanner 扫描仪sensor 传感器sophisticate 复杂typewriter 打字机venerable 庄严的

·198·23/4/21 计算机专业英语 198

Notes

[1]    What a computer program produces is a stream of coded symbols.

本句中的“What a computer program produces”作主语。译文：计算机程序产生的是编码的符号流。[2]    The arrow keys allow you to move the position of the cursor on the screen.

本句中的不定式结构“ to move the position of the cursor on the screen”作宾语补足语。译文：方向键允许你移动光标在屏幕上的位置。

·199·23/4/21 计算机专业英语 199

Notes

[3]    The second button, on the right, usually provides some less-frequently needed capability.

本句的“ on the right” 是同位语，进一步说明主语。译文：第二个按键在右边，提供了某些不太常用的功能。[4]    In interlace style, electron-beam sweeps elements in odd rows first time and does elements in even rows second time.

本句中的 electron-beam 译作电子射枪， elements 译作像素。译文：在隔行方式中，电子射枪首先扫描奇数项中的像素，第二次再扫描偶数项中的像素。

·200·23/4/21 计算机专业英语 200

Notes

[5] To edit text read by an optical scanner, you need an optical character recognition (OCR) system to translate the image into ASCII characters.

本句的“ To edit text read by an optical scanner” 是目的状态，而“ to translate …”是宾语补足语。译文：要编辑由光学扫描仪读入的文本，你需要一套光学字符识别系统（ OCR ）将图像翻译成 ASCII码。

·201·23/4/21 计算机专业英语 201

词组翻译练习

(1)  基于字符的显示器 character-based diaplay

(2)  隔行及非隔行 interlace and non-interlace

(3)  布局 layout

(4)  输入 /输出设备 input/output device

(5)  功能键 function key

(6)  光标 cursor

(7)  像素距离 element distance

(8)  分辨率 solution

·202·23/4/21 计算机专业英语 202

Reading material :Printer

Printers are used to produce a paper or hard copy of the processing results. There are several types of printers with tremendous differences in speed, print quality, price and special features.

Dot-Matrix Impact Printers Dot-Matrix Thermal Printers Laser Printers Ink-Jet Printers

·203·23/4/21 计算机专业英语 203

Execution of a program

The typical operations that take place in the processing of instructions are part of either the instruction cycle or the execution cycle.

The instruction cycle, or I-cycle, refers to the retrieval of an instruction from main memory and its subsequent decoding (the process of altering the circuits in

main memory and its subsequent decoding (the process of altering the circuits in the CPU to perform the specified operation). The time it takes to go through the instruction cycle is referred to as I-time.

The execution cycle, or E-cycle, refers to the execution of the instruction and the subsequent storing of the result in a register. The time it takes to go through the execution cycle is referred to as E-time. The instruction cycle and the execution cycle together, as they apply to one instruction, are referred to as a machine cycle. The CPU as an internal clock synchronizes all operations in the cycle. The speed is expressed in megahertz (MHZ). 1MHZ equals 1 million cycles per second. Generally, the faster the clock speed, the faster the computer can process information. Of course, for most users the faster, the better, and the more expensive.

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Execution of a program

The basic machine cycle is repeated over and over again, until all the instructions in the program have been executed.

I-time: control unit fetches instruction

E-time: ALU execute instruction

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2.5 Parallel Organization

Multiprocessing Organization Time-Shared Bus Multi-port Memory Central Control Unit Goals of Parallel Processing

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Multiprocessing

The use of multiple processors is motivated by considerations of performance and reliability.

We can classify such systems as follows: Loosely Coupled Multiprocessing Functionally Specialized Processors Tightly Coupled Multiprocessing Parallel Processing

·207·23/4/21 计算机专业英语 207

The key characteristics of a multiprocessor

It contains two or more similar general-purpose processors of comparable capability.

All processors share access to global (common) memory. Some local (private) memory may also be used.

All processors share access to I/O devices, either through the same channels or through different channels that provide paths to the same devices.

The system is controlled by an integrated operating system that provides interaction between processors and their programs that the job, task, file, and data element levels.

·208·23/4/21 计算机专业英语 208

Organization

A multiprocessor system has two or more CPUs in general. Each CPU is self-contained, including a control unit, ALU, registers, and,

possibly, cache. Each CPU has access to a shared main memory and the I/O devices through

some form of interconnection mechanism. The organization of a multiprocessor system can be classified as Time-Shared

or Common Bus, Multi-port Memory and Central Control Unit.

·209·23/4/21 计算机专业英语 209

Time-Shared Bus

The time-shared bus is the simplest mechanism for constructing a multiprocessor system.

The structure and interfaces are basically the same as for a single-processor system that uses a bus interconnection.

The bus consists of control, address, and data lines.

·210·23/4/21 计算机专业英语 210

The bus organization has several advantages compared to other approaches

Simplicity: The physical interface and the addressing, arbitration, and time-sharing logic of each processor remain the same as in a single-processor system.

Flexibility: It is generally easy to expand the system by attaching more CPUs to the bus.

Reliability: The bus is essentially a passive medium, and the failure of any attached device should not cause failure of the whole system.

·211·23/4/21 计算机专业英语 211

Multi-port Memory

The multi-port memory approach allows the direct, independent access of main memory modules by each CPU and I/O module.

The multi-port memory approach is more complex than the bus approach, requiring a fair amount of logic to be added to the memory system.

It should, however, provide better performance since each processor has a dedicated path to each memory module.

Another advantage of multi-port is that it is possible to configure portions of memory as “private” to one or more CPUs and/or I/O modules.

·212·23/4/21 计算机专业英语 212

Central Control Unit

The central control unit is an extension of the system controller concept. The controller can buffer requests and perform arbitration and timing functions. It can also pass status and control messages between CPUs and perform cache

update alerting.

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Goals of Parallel Processing

Reduce User’s Time Cheapest Possible Solution strategy Local versus Non-local Resources Memory Constraints

·214·23/4/21 计算机专业英语 214

Key Words

aggregate 合计，总计alleviate 减轻，使缓和arbitration 仲裁，公断autonomous 自治的computationally 计算地conflict 冲突，战争constraint 强制，约束cooperatively 合作地，协作的dramatically 戏剧地，突然地elaborate 详细说明facilitate 使容易，促进

·215·23/4/21 计算机专业英语 215

Key Words

feature 特征，特色flexibility 适应性latency 潜伏，潜在parallelism 并行的proportionally 成比例地，相称地reliability 可靠性simplicity 简单，简朴somewhat 某物strategy 策略，战略submit 提交susceptible 易受影响的

·216·23/4/21 计算机专业英语 216

Notes

[1] As computer technology has evolved, and as the cost of computer hardware has dropped, computer designers have sought more and more opportunities for parallelism, usually to improve performance and, in some cases, to improve reliability.

本句由“ As”引导原因状语从句，“ and as the cost …” 是同位语，表示另一个原因，“ in some cases” 是插入语。译文：随着计算机技术的发展以及计算机硬件价格的降低，计算机的设计者开始寻找越来越多并行操作的机会，通常是为了提高操作效率，以及在某些情况下提高可靠性。

·217·23/4/21 计算机专业英语 217

Notes

[2] The memory is often organized so that multiple simultaneous accesses to separate blocks of memory are possible.

本句由“ so that”引导目的状语从句。译文：通过对内存的组织，对内存不同分块的同时操作变为可行。[3] When one module is controlling the bus, other modules are locked out and must, if necessary, suspend operation until bus access is achieved.

本句由“When”引导时间状语从句，“ if necessary” 是插入语。译文：当一个模块在控制总线时，其他的模块被锁定，而且在必要时要将其操作悬挂，直到总线的存取能够实现为止。

·218·23/4/21 计算机专业英语 218

Notes

[4] The multi-port memory approach is more complex than the bus approach, requiring a fair amount of logic to be added to the memory system.

本句由“more…than” 实现比较，“ requiring a fair…” 是现在分词短语作主语补足语。译文：多端口内存技术比总线技术要复杂，需要给内存加上相当数量的逻辑。

·219·23/4/21 计算机专业英语 219

词组翻译练习

(1)  高速缓冲存储器 cache memory

(2)  数据流 data stream

(3)  单处理器 single-processor

(4)  多端口存储器 multi-port memory

(5)  公共数据区 common data area

(6)  松耦合多处理器 loosely coupled multiprocessing

(7)  输入 /输出处理器 I/O processor

(8)  集成控制 integrated control

·220·23/4/21 计算机专业英语 220

Reading Material ： Multiprocessing

A system in which each processor has a private (local) main memory and shares secondary (global) memory with the others is a secondary memory multiprocessor.

The more common multiprocessor systems incorporate only processors of the same type and performance and thus are called homogeneous multiprocessors.

·221·23/4/21 计算机专业英语 221

The types of multiprocessor systems

Multiprocessor systems may be classified into four types: single instruction stream, single data stream (SISD); single instruction steam, multiple data stream (SIMD); multiple instruction stream, single data stream (MISD); multiple instruction stream, multiple data stream (MIMD).

·222·23/4/21 计算机专业英语 222

第 3 章 Software Knowledge

3.1 Data Structures

3.2 Operating System

3.3 Programming Languages

3.4 Software Engineering

3.5 Software Testing and Maintenance

·223·23/4/21 计算机专业英语 223

3.1 Data Structures

General data structure types include the array, the file, the record, the table, the tree, and so on.

In computer programming, a data structure may be selected or designed to store data for the purpose of working on it with various algorithms.

If we provide a set of possible data values and a set of operations that act on the values, we can think of the combination as a data type.

We will call any data type whose values are composed of component elements that are related by some structure a structured data type, or data structure.

·224·23/4/21 计算机专业英语 224

Integer

Integer is amounts to a particular collection of axioms or rules that must be obeyed.

The way in which integers are represented is unimportant provided only that all readers understand the notation—binary, octal, decimal, hexadecimal, twos complement, ones complement or sign and magnitude, the choice does not matter.

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List

The list is a flexible abstract data type. It is particularly useful when the number of elements to be stored is not known

before running a program or can change during running. It is well suited to sequential processing of elements because the next element

of a list is readily accessible from the current element. It is less suitable for random access to elements as this require a slow linear

search.

·226·23/4/21 计算机专业英语 226

Array and Record

The data types arrays and records are native to many programming languages. By using the pointer data type and dynamic memory allocation, many

programming languages also provide the facilities for constructing linked structures.

Arrays, records, and linked structures provide the building blocks for implementing what we might call higher-level abstractions.

·227·23/4/21 计算机专业英语 227

Stack

A stack is a data type whose major attributes are determined by the rules governing the insertion and deletion of its elements.

The only element that can be deleted or removed is the one that was inserted most recently.

Such a structure is said to have a last-in/first-out (LIFO) behavior, or protocol. The sequencing of calls to and returns from subroutines follows a stack

protocol.

·228·23/4/21 计算机专业英语 228

Queue

The main feature of queues is that they follow a first-come/first-served rule. In queues the earliest element inserted is the first served. In social settings, the rule appeals to our sense of equality and fairness.

In computer systems, events that demand the attention of the computer are often handled according to a most-important-event/first-served, or highest-priority in/first-out (HPIFO), rule. Such queues are called priority queue, in this type of queue service is not in order of time of arrival but rather in order of some measure of priority.

·229·23/4/21 计算机专业英语 229

The data structure of object-oriented software

From the point of view of deciding which data structure should represent that attributes of objects in a specific class, the emphasis that the object –oriented approach places on abstraction is very important to the software development process.

Abstraction means hiding unnecessary details. Once an appropriate abstraction is selected, there may be several choices for

representing the data structure. After an abstraction and representation are chosen, there are competing

methods to encapsulate data structures.

·230·23/4/21 计算机专业英语 230

Key Words

abstract 抽象，摘要accessible 易进入的，可使用的arithmetic 算术，算法axiom 公理，原理behavior 行为，举止contemporary 同时代的devoid 全无的，缺乏的encapsulate 封装，压缩identifiable 可以确认的instantiate 例示

·231·23/4/21 计算机专业英语 231

Key Words

integrity 完整，正直irrelevant 无关系的，不相干的magnitude 重大，重要notation 记号，符号object-oriented 面向对象的sequential 后继的stack 栈，堆栈tradeoff 交换，平衡，交易underlying 在下面的versus 对……

·232·23/4/21 计算机专业英语 232

Notes

[1] The essence of a data type is that it attempts to identify qualities common to a group of individuals or objects that distinguish it as an identifiable class or kind.

本句由两个复合句构成，均由 that引导。第一个 that引导表语从句；第二个 that引导限定性定语从句，修饰 qualities ， it代表 a group of individuals or objects 。译文：数据类型的本质是标识一组个体或目标所共有的特性，这些特性把该组个体作为可识别的种类。

·233·23/4/21 计算机专业英语 233

Notes

[2] A data structure is a data type whose values are composed of component elements that are related by some structure.由 whose 引导的限定性定语从句修饰 a data type ， that引导的限定性定语从句修饰component elements 。译文：数据结构是一种数据类型，其值是由与某些结构有关的组成元素所构成的。[3] Many computer systems have stacks built into their circuitry and have machine-level instructions to operate the hardware stack.本句中，过去分词短语 built into their circuitry作定语，修饰 stacks；动词不定式短语to operate the hardware stack也作定语，修饰machine-level instructions 。译文：许多计算机系统的电路中都含有多个栈，并且含有操作硬件栈的机器指令。

·234·23/4/21 计算机专业英语 234

Notes

[4] Procedural abstraction, or algorithmic abstraction, is hiding of algorithmic details, which allows the algorithm to be seen or described, at various levels of detail.

本句中的“ or algorithmic abstraction” 是同位语，“ which allows the algorithm to be seen or described”也是同位语。译文：过程抽象或算法抽象是隐藏算法细节的，允许算法在各个细节层次上可见或被描述。[5] Once an appropriate abstraction is selected, there may be several choices for representing the data structure.

本句由“ Once”引导时间状语从句。译文：一旦选择了一个合适的抽象，就有一些选择来表示数据结构。

·235·23/4/21 计算机专业英语 235

词组翻译练习

(1)  自由访问 random access

(2)  数据类型 data type

(3)  数据结构 data structure

(4)  数据值 data value

(5)  二进制和十六进制 binary and hexadecimal

(6)  抽象数据类型 abstract data type

(7)  后进先出 last-in / first-out

(8)  算术表达式 arithmetic expression

·236·23/4/21 计算机专业英语 236

Reading Material ：Applications of stack and queue

When a call is made to a new function, all the variables local to the calling routine need to be saved by the system, since otherwise the new function will overwrite the calling routine’s variables.

It is frequently the case that stacks do not share components and then it is usual to write pop and push procedures.

There are many applications of the first-in/first-out (FIFO) protocol of queues in computing.

There are several algorithms that use queues to give efficient running times.

·237·23/4/21 计算机专业英语 237

Database Technology

A database-management system (DBMS) consists of a collection of interrelated data and a set of programs to access those data.

The collection of data, usually referred to as the data-base, contains information about one

particular enterprise.

The primary goal of a DBMS is to provide an environment that is both convenient and

efficient to use in retrieving and storing database information.

·238·23/4/21 计算机专业英语 238

Database systems are designed to manage large bodies of information. The management of data involves both the definition of structures for the storage of information and the provision of mechanisms for the manipulation of information.

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In addition, the database system must provide for the safety of the information stored, despite system crashes or attempts at unauthorized access. If data are to be shared among several users, the system must avoid possible anomalous results.

·240·23/4/21 计算机专业英语 240

The importance of information in most organizations-which determines the value of the database-has led to the development of a large body of concepts and techniques for the efficient management of data.

·241·23/4/21 计算机专业英语 241

The storage structure and access methods used by the database system are specified by a set of definitions in a special of DDL called a data storage and definition language. The result of compilation of these definitions is a set of instructions to specify the implementation details of the database schemas-details are usually hidden from the users. A database schema is also specified by DDL.

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The result of compilation of DDL statements is a set of tables that is stored in a special file called data dictionary, or data directory. A data dictionary is a file that contains metadata-that is, data about data. This file is consulted before actual data are read or modified in the database system.

·243·23/4/21 计算机专业英语 243

Transaction Management

A transaction is a collection of operations that performs a single logical function in a database application. Each transaction is a unit of both atomicity and consistency. Thus, we require that transactions do not violate any database-consistency constraints.

·244·23/4/21 计算机专业英语 244

That is, if the database was consistent when a transaction started, the database must be consistent when the transaction successfully terminates. However, during the execution of a transaction, it may be necessary temporarily to allow inconsistency. This temporary inconsistency, although necessary, may lead to difficulty if a failure occurs.

·245·23/4/21 计算机专业英语 245

It is the responsibility of the programmer to define properly the various transactions, such that each preserves the consistency of the database. For example, the transactions to transfer funds from account A to account B could be defined to be composed of two separate programs: one that debits account A, and an another that credits account B.

·246·23/4/21 计算机专业英语 246

The execution of these two programs one after the other will indeed preserve consistency. However, each program by itself does not transform the database from a consistent state to a new consistent state. Thus, those programs are not transactions.

·247·23/4/21 计算机专业英语 247

Ensuring the atomicity and durability properties is the responsibility of the database system itself-specifically, of the transaction-management component. In the absence of failures, all transactions complete successfully, and atomicity is achieved easily.

·248·23/4/21 计算机专业英语 248

3.2 Operating System

The purpose of an operating system is to provide an environment in which a user may execute programs.

Operating systems exist because they are a reasonable way to solve the problem of creating a usable computing system.

The primary goal of an operating system is convenience for the user. A secondary goal is efficient operation of the computer system.

·249·23/4/21 计算机专业英语 249

Resource Management

The operating system provides the means for the proper use of these resources in the operation of the computer system.

We can view an operating system as a resource allocates. The operating system sets up the order in which programs are processed, and

defines the sequence in which particular jobs are executed.

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I/O Management

To facilitate execution of I/O operations, most operating systems have a standard set of control instructions to handle the processing of all input and output instructions.

These standard instructions, referred to as the input/output control system (IOCS), are an integral part of most operating systems.

The controlling software calls on the IOCS software to actually complete the I/O operation.

·251·23/4/21 计算机专业英语 251

Classification of Operating Systems

A single-user operating system expects to deal with one set of input devices—those that can be controlled by one user at a time.

A multi-user operating system is designed to deal with input, output, and processing requests from many users-all at the same time.

A network operating system provides communications and routing services that allow computers to share data, programs and peripheral devices.

·252·23/4/21 计算机专业英语 252

Classification of Operating Systems

A multitasking operating system provides process and memory management services that allow two or more programs to run simultaneously.

All modern operating systems are multitasking and can run several processes simultaneously.

A desktop operating system is one that is designed for a personal computer—either a desktop or notebook computer.

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Key Words

accommodate 使适应assess 评估context switching 上下文转接，任务切换convenience 方便，便利efficient 有效的environment 环境fundamental 基本的，原则government 政府

·254·23/4/21 计算机专业英语 254

Key Words

handle 操作，处理interface 接口，界面primary 主要的，根本的primitive 原始的，基本的scheduler 调度程序，调度表statement 陈述，指令，语句suspend 暂停，挂起workstation 工作站

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Notes

[1] An operating system is a program, which acts as an interface between a user of a computer and the computer hardware.

本句由“ which”引导非限定性定语从句，修饰“ program” 。译文：操作系统是一种程序，它是用户与计算机硬件之间的接口。[2] The fundamental goal of computer systems is to execute user programs and solve user problems.

本句由不定式结构“ to execute …”作表语。译文：计算机系统的基本目标是执行用户程序和解决用户问题。

·256·23/4/21 计算机专业英语 256

Notes

[3] Operating system exists because they are supposed to make it easier to compute with an operating system than without an operating system.

本句由“ because”引导原因状语从句，用“ than” 实现比较。译文：操作系统的存在是因为有操作系统比没有操作系统计算更容易。[4] A single-user operating system expects to deal with one set of input devices—those that can be controlled by one user at a time.

本句的“ those that can be controlled by one user at a time” 是同位语。译文：单用户操作系统是用来处理一组输入设备，那些能被一个用户在同一时刻控制的设备。

·257·23/4/21 计算机专业英语 257

Notes

[5] The most common mechanism used to create this illusion is time slice multitasking, whereby each process is run individually for a fixed period of time.

过去分词短语 used to create this illusion作定语，修饰mechanism；由 whereby引导的是非限制性定语从句。 whereby ： by means of which ，以…方式；凭借。译文：产生这种错觉的最常用机制是时间分割多任务处理，以每个过程各自运行固定的一段时间的方式来实现的。

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词组翻译练习

(1)  资源 resource

(2)  多用户系统 multi-user system

(3)  单任务 single-task

(4)  桌面操作系统 desktop operating system

(5)  个人计算机 personal computer

(6)  多任务操作系统 multitasking operating system

(7)  笔记本电脑 notebook computer

(8)  作业队列 job queue

·259·23/4/21 计算机专业英语 259

Reading Material ：Windows XP Technical Overview

The Windows operating system gets its name from the rectangular work areas that appear on the screen-based desktop.

Each area can display a different document or program, providing a visual model of the operating system’s multitasking capabilities.

Windows XP is the next version of Microsoft Windows beyond Windows 2000 and Windows Millennium.

Windows XP is built on an enhanced Windows 2000 code base, with different versions aimed at home users and business users: Windows XP Home Edition and Windows XP Professional.

·260·23/4/21 计算机专业英语 260

The characteristics of Windows XP

Fast User Switching for Multiple Users of a Computer New Visual Style User Interface Enhances Productivity Windows Media Player 8 64-Bit Support

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3.3 Programming Languages

A programming language or computer language is a standardized communication technique for expressing instructions to a computer.

A language enables a programmer to precisely specify what data a computer will act upon, how these data will be stored/transmitted, and what actions to take under various circumstances of cases.

Programming languages are important tools for helping software engineers write better programs faster.

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Procedural programming and Object-oriented programming

Procedural programming involves using your knowledge of a programming language to create computer memory locations that can hold values and writing a series of steps or operations that manipulate those values.

A single procedural program often contains hundreds of variable and thousands of procedure calls.

Object-oriented programming is an extension of procedural programming in which you take a slightly different approach to writing computer programs.

Writing object-oriented programs involves both creating objects and creating applications that use those objects.

·263·23/4/21 计算机专业英语 263

Machine Language

An executable program is a sequence of extremely simple instructions known as machine code.

Machine code instructions are binary—that is, sequences of bits (0s and 1s). Because these numbers are not understood easily by humans, computer

instructions usually are not written in machine code.

·264·23/4/21 计算机专业英语 264

Assembly Language

Assembly language uses commands that are easier for programmers to understand than are machine-language commands.

Each machine language instruction has an equivalent command in assembly language.

Assembly language is sometimes inserted into a high-level language program to carry out specific hardware tasks or to speed up a high-level program.

·265·23/4/21 计算机专业英语 265

High-Level Languages

If the computer could translate convenient symbols into basic operations, why couldn’t it also perform other clerical coding functions?

A high-level programming language is a means of writing down, in formal terms, the steps that must be performed to process a given set of data in a uniquely defined way.

The high-level languages are often oriented toward a particular class of processing problems.

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Compiler and Interpreter

A complier is a program that translates source code into object code. Every high-level programming language comes with a compiler. Because compilers translate source code into object code, which is unique for

each type of computer, many compilers are available for the same language. An interpreter translates high-level instructions into an intermediate form, which

it then executes. The advantage of an interpreter, however, is that it does not need to go through

the compilation stage during which machine instructions are generated.

·267·23/4/21 计算机专业英语 267

Key Words

assembler 汇编程序，汇编器circumstance 环境，状况clerical 文书上的compilation 编辑correspondence 相应employee 职员，员工envision 想象equivalent 相等的，相当的federal 联合的，同盟的instruction 指令invoke 引起，实行

·268·23/4/21 计算机专业英语 268

Key Words

multiply 乘，增加precisely 精确地roughly 粗略地semantic 语义的specify 指定，说明standardized 标准化symbol 符号syntactic 句法的syntax 语法uniquely 独特地，独一无二地variable 变量

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Notes

[1] Procedural programming involves using your knowledge of a programming language to create computer memory locations that can hold values and writing a series of steps or operations that manipulate those values.

本句用动名词短语“ using your knowledge”作宾语，“ to”引导的不定式结构作宾语补足语。“ that”引导定语从句修饰“ locations” 。译文：面向过程的程序设计包括用程序设计语言建立存放值的存储单元，编写对这些值进行运算的一系列步骤或操作。

·270·23/4/21 计算机专业英语 270

Notes

[2] Computer programs that can be run by a computer’s operating system are called executables.本句中的“ that can be run by a computer’s operating system” 是主语“ Computer programs” 的定语从句，用被动语态表示客观性。译文：能被计算机操作系统直接运行的计算机程序称为可执行程序。[3] Let us now look at the features we would expect to find in a high-level language and how they compare with machine code and assembly language.we would… 为省略了引导词 that 的限定性定语从句，修饰和限定 features ； and连接的是 look at 的第二宾语从句： how they…到句末。译文：现在可以来看看人们所期望的高级语言应有的特点以及怎样将它们与机器码和汇编语言进行比较。

·271·23/4/21 计算机专业英语 271

Notes

[4] There are two ways to run programs written in a high-level language.

这是一个“ there be” 句型，是倒装句，过去分词短语“ written in a high-level language”作定语。译文：有两种方法运行高级语言编写的程序。[5] Compiled programs generally run faster than interpreted programs.

本句用过去分词“ Compiled”作定语，修饰主语“ programs” ，用“ than”连接比较的两部分。译文：编译程序通常比解释程序运行的更快。

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词组翻译练习

(1)  机器码 machine code

(2)  机器语言 machine language

(3)  面向过程的程序 procedural program

(4)  汇编语言指令 assembly language instruction

(5)  抽象代码 abstract code

(6)  位序列 sequences of bits

(7)  源代码 source code

(8)  高级语言 high-level language

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Reading Material ： A Brief Introduction of Programming Languages

C FORTRAN C++ JAVA JavaScript VB Delphi PowerBuilder C#

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C language

C was developed in the early 1970s. C is a general-purpose, structured programming language.

C might best be described as a “medium-level language.” Unlike most high-level language, C lets you easily do chores (such as bit and

pointer manipulation) additionally performed by assembly language. Therefore, C is an especially good tool to use for developing operating system

(such as the UNIX operating system), or other system software.

·275·23/4/21 计算机专业英语 275

FORTRAN

FORTRAN was made up by two words: Formula and Translate, and it means interpreting formula.

The first FORTRAN language was developed in 1957, and improved to the structural language in the next 1977 years, called FORTRAN 77.

After the object-oriented idea and indicator was offered, the function of the array was strengthened, and the pattern of old edition FORTRAN was improved in 1991, it is called FORTRAN 90.

·276·23/4/21 计算机专业英语 276

C++

C++ fully supports object-oriented programming, including the four pillars of object-oriented development: encapsulation, data hiding, inheritance, and polymorphism.

While it is true that C++ is a superset of C, and that virtually any legal C program is a legal C++ program, the leap from C to C++ is very significant.

C++ benefited from its relationship to C for many years, as C programmers could ease into their use of C++.

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JAVA

In brief, Java environment can be used for developing the application software that can be operated on any computing platform.

It is a kind of basic technology with compact structure in fact, and its overall influence on World Wide Web and commerce can correctly be compared with the impact of electronic form on PC.

·278·23/4/21 计算机专业英语 278

JavaScript

JavaScript is an adaptation of Netscape’s own scripting language. It consists of Java like commands that exist within the HTML. JavaScript provides a relatively complete set of built in functions and

commands that allow the user to perform various functions. One of the most powerful attributes of JavaScript is that when a web page is

downloaded with JavaScript embedded, the JavaScript is executed on the users computer rather than having to communicate with the server.

·279·23/4/21 计算机专业英语 279

Visual Basic

VB is fast visual procedure developing software that Microsoft produced. Supported by the monopoly position of Microsoft in the operating system and

software, VB sweeps across the whole world within a few years. VB is the extremely characteristic and powerful software, mainly showing in the

following aspects: the interface design of WYSWYG, object-oriented design method, extremely short development period, and formulation code relatively apt to maintain.

·280·23/4/21 计算机专业英语 280

Delphi

Delphi is a new development environment object-oriented visual application program Inprise Company (former Borland Company) developed.

It works on Windows 95/98 or Windows NT operating system. Delphi is an integrated development environment (IDE) using Object Pascal language developed by traditional Pascal language.

It is a code editing machine instead of a kind of language in essence, but because Delphi is nearly the only piece of products which uses Pascal language on the market, Delphi has become the pronoun that people sometimes call Object Pascal.

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PowerBuilder

PowerBuilder is a powerful and excellent developing instrument put out by Powersoft Company, famous database manufacturer in U.S.A. in June 1991.

It is a kind of object-oriented, visual figure interface, fast mutual instrument. The intelligent data window object is the quintessence.

You can utilize this object to operate the data of the relation database, not need to write SQL sentence, namely it can search, upgrade and display the data in the data source with the various forms directly.

·282·23/4/21 计算机专业英语 282

C#

C# is a new programming language for. Net platform design developed by Microsoft, the most close to.

Net language at present. Using C#, you can write one dynamic webpage, design one component or traditional window application program, etc.

C# is a composite language between literality language and compiling language (no matter efficiency of carrying out or procedure simplicity).

·283·23/4/21 计算机专业英语 283

3.4 Software Engineering

Software engineering is the application of tools, methods, and disciplines to produce and maintain an automated solution to a real-world problem.

Software engineering first emerged as a popular term in the title of a 1968 NATO conference held in Garmisch, Germany.

A large-scale software projects spans a considerable period of time. A number of distinct phases can be identified over this period of time. Together, these make up what is known as the “software life cycle”.

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The software life cycle

1. Requirements definition: The requirements of the software are established and specified.

2. Design: A design is developed from an analysis of the requirements.

3. Implementation: The design is coded in a particular programming language on a particular machine.

4. Testing: The implemented system is tested to see that it meets the specified requirements.

5. Operation and maintenance: The system is installed and used. Errors found must be repaired.

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Requirements definition

The first phase, requirements definition, refers to the period during which the requirements of the system desired, that is, it’s functional characteristics and operational details, are specified.

The input to this phase is the stated (often rather loosely stated) needs for the software.

Typically, a “requirements document” is the output of this phase, a set of precisely stated properties or constraints that the final product must satisfy.

As with any of the phases, it is important that errors not be allowed to move into subsequent phases.

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Design

The second phase, design, is predominantly creative, while some would argue that creativity is inherent and cannot be trained or improved, it can certainly be enhanced by the use of good procedures and tools.

The input to this phase is a (debugged and validated) requirements document: the output is a design expressed in some appropriate form (for example, pseudo-code).

Each requirement in the requirements document must have a corresponding design fragment to meet it.

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Implementation

The third phase, implementation, is the actual coding of the design developed in the second phase.

The lure of this phase is strong, and many a foolhardy programmer has been drawn to it before adequately laying the groundwork in the first two phases.

As a result, requirements are incompletely understood and the design is flawed.

The implementation proceeds blindly, and many problems arise as a result.

·288·23/4/21 计算机专业英语 288

Testing

The fourth phase, testing, is concerned with demonstrating the correctness of the implemented program. Inevitably some testing is performed as part of the previous two phases as well.

Any experienced programmer mentally tests each line as it is produced and mentally simulates the execution of any module prior to any formal testing stage.

A “successful” test run means only that no errors were uncovered with the particular circumstances tested; it says nothing about other circumstances.

In theory, the only way that testing can show that a program is correct is if all possible cases are tried (known as an exhaustive test), a situation technically impossible for even the simplest programs.

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Program maintenance

The fifth phase is program maintenance phase. Student programmers, unfortunately, rarely become involved in this phase.

Its importance in the real world, however, cannot be overemphasized, since the cost of maintaining a widely used program can match or exceed the cost of developing it.

Unlike hardware maintenance, software maintenance deals not with repair of deteriorated components, but with repair of design defects, which may include the provision of added functions to meet new needs.

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Key Words

aspiration 渴望，志向boundary 边界，分界线budget 预算emerge 出现，形成flaw 缺点，瑕疵foolhardy 有勇无谋的fragment 碎片，片段inadequate 不充分的，不适当的inevitably 不可避免地judiciously 头脑精明地，判断正确地juxtaposition 并列，并置lure 诱惑，引诱

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Key Words

NATO (North Atlantic Treaty Organization) 北大西洋公约组织overrun 泛滥成灾，超出限度predominantly 占主导地位，支配prototype 原型provocative 引起争论的reveal 显示，揭露span 跨距，一段时间substantial 实质上的sufficient 充分的，足够的terminology 术语，术语学threaten 威胁validate 证实，验证verification 证实，查证

·292·23/4/21 计算机专业英语 292

Notes

[1] Consequently, software engineering emerged as the organizing force to overcome the barriers that threatened our progress.

本句中， as the organizing force 为方式状语，不定式短语 to overcome the barriers 作organizing force 的定语，由 that引导的定语从句修饰 barriers 。译文：因此，软件工程是作为一种克服那些阻碍我们进步的障碍的组织力量而出现的。[2] More informal revolve the entire design team, management, and even the client.

本句中的“ the entire design team” 、“management” 和“ the client”并列作宾语。“ More informal” 表示“More informal verification” 。译文：更多的是整个的设计团队、管理者甚至是客户的非正式的校阅。

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Notes

[3] Any experienced programmer mentally tests each line as it is produced and mentally simulates the execution of any module prior to any formal testing stage.本句的并列谓语为“ test” 和“ simulate” 。译文：任何有经验的程序员都在内心里测试每一行产生的语句并在正式测试之前在心里已经模拟了任何模块的执行过程。[4] The ability of programmers to produce new programs is clearly affected by the amount of time they spend maintaining old ones.本句中的“ to produce new programs”作“ programmers” 的定语，而“ they spend maintaining old ones”作“ time” 的定语。译文：程序员开发新的软件的能力无疑的受到了维护旧软件时间长短的影响。

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词组翻译练习

(1)  软件工程 software engineering

(2)  软件产品 software product

(3)  软件危机 software crisis

(4)  软件生命周期 software life cycle

(5)  伪代码 pseudo code

(6)  硬件维护 hardware maintenance

(7)  软件维护 software maintenance

(8)  现实世界问题 real-world problem

·295·23/4/21 计算机专业英语 295

Reading Material ： The software life cycle

In the earliest stages, and in the last stages, of the lifecycle, software architecture, requirements, and system definition is an issue.

The waterfall model is a software development model first proposed in 1970, in which development proceeds linearly through the phases of requirements analysis, design, implementation, testing (validation), integration and maintenance.

The classic life cycle is the oldest and the most widely used paradigm for software engineering.

However, over the past few years, criticism of the paradigm has caused even active supporters to question its applicability in all situations.

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3.5 Software Testing and Maintenance

We test a program in order to demonstrate the existence of an error. Because our goal is to discover errors, we can consider a test successful only

when an error is discovered. Once an error is found, “debugging” or error correction is the process of

determining what causes the error and of making changes to the system so that the error no longer exists.

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Stages of Testing

First, each program module is tested as a single program, usually isolated from the other programs in the system.

Unit testing is done in a controlled environment whenever possible so that the test team can feed a predetermined set of data to the module being tested and observe what output data are produced.

Integration testing is the process of verifying that the components of a system work together as described in the program design and system design specifications.

·298·23/4/21 计算机专业英语 298

Stages of Testing

A function test evaluates the system to determine if the functions described by the requirements specification are actually performed by the integrated system.

A performance test compares the system with the remainder of the software and hardware requirements.

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Software Maintenance

Maintenance begins after the system is released. As people use it, they will suggest minor improvements and enhancements.

Maintenance activities involve making enhancements to software products, adapting products to new environments, and correcting problems.

It should also be observed that software maintenance is a microcosm of the software development cycle.

Analysis activities during software maintenance involve understanding the scope and effect of a desired change, as well as the constraints on making the change.

Design during maintenance involves redesigning the product to incorporate the desired changes.

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Key Words

acceptance 接受，同意adequacy 适当，足够delivery 递送，交付demonstration 示范，实证expectation 期待，指望functionality 功能性isolate 隔离，孤立maintainability 维护性microcosm 小宇宙，小世界occasionally 有时候，偶尔periodic 周期的，定期的

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Key Words

predetermine 预先决定prescription 命令，指令perspective 远景，看法recall 回忆，回顾reflect 反映，反射release 释放，发行remainder 剩余的reverse 相反，背面systematic 有系统的，体系的

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Notes

[1] No matter how capably we write programs, it is clear from the variety of possible errors that we should check to insure that our modules are coded correctly.

本句由“ No matter how”引导让步状语从句，“ it” 是形式主语，“ that we should …”是主语从句。 译文：无论我们写的程序多好，我们显然都应该检查各种各样可能发生的错误来保证模块编码的正确。[2] In the development of a large system, testing involves several stages.

本 句 的 介 词 短 语“ In the development of a large system” 作条件状 语 ， 动 名词“ testing”作主语。译文：在一个大系统的开发中，测试包括若干个阶段。

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Notes

[3] When the performance test is complete, we as developers are certain that the system functions according to our understanding of the system description.

“When the performance test is complete” 是时间状语从句，“ developers”作“ we”的同位语。译文：当执行测试完成后，作为开发人员的我们要确保系统功能与我们对系统描述的理解相一致。

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Notes

[4] If maintenance consumes 70 percent of the total life-cycle effort devoted to a particular software product, and if 60 percent of maintenance goes to enhancing the product, then 42 percent of the total life-cycle effort for that product is dedicated to product enhancement.

本句有两个并列的由“ if”引导的条件状语从句。译文：如果一个特定的软件产品的维护耗费了整个生命周期的 70% 的工作量，其中有60% 用于改进产品，那么，整个生命周期中有 42% 的工作用于软件改进上。

·305·23/4/21 计算机专业英语 305

词组翻译练习

（ 1 ）内部数据结构 internal data structure

（ 2 ）边界条件 boundary condition

（ 3 ）仿真环境 simulated environment

（ 4 ）维护阶段 maintenance phase

（ 5 ）软件开发 software development

（ 6 ）用户手册 user’s manual

（ 7 ）集成测试 integration testing

（ 8 ）软件测试 software testing

·306·23/4/21 计算机专业英语 306

Reading Material ：Evolution of Software Engineering

Software engineering is the discipline of producing software to meet customer needs with the highest quality feasible given resource constraints.

It is concerned with the ways in which people conduct their work activities and apply technology to produce and maintain software products and software-intensive systems.

Software engineering is essential for anyone working in development, maintenance, management, or related areas in a software organization.

·307·23/4/21 计算机专业英语 307

The development of software engineering

1945 to 1965: The origins 1965 to 1985: The software crisis 1985 to 1995: No silver bullet 1995 to present: emergence as a profession

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第 4 章 Computer Network Knowledge

4.1 Computer Networking Concepts

4.2 The OSI Reference Model

4.3 Internet Overview

4.4 Internet Security

4.5 E-commerce

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4.1 Computer Networking Concepts

Computer network can be used for numerous services, both for companies and for individuals.

Networks can be divided up into LANs, MANs, WANs, and Internet works, each with their own characteristics, technologies, speeds, and niches.

Network software consists of protocols, or rules by which processes can communicate.

Network establishes communication among computers. This system is especially helpful when people work on different place.

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Local Area Networks (LANs)

A local area networks, or LAN, is a communication network that is privately owned and that covers a limited geographic area such as an office, a building, or a group of building.

The LAN consists of a communication channel that connects either a series of computer terminals together with a minicomputer or, more commonly, a group of personal computers to one another.

Two common applications of local area networks are hardware resource sharing and information resource sharing.

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Wide Area Networks (WANs)

A wide area network, or WAN, is geographic in scope (as opposed to local) and uses telephone lines, microwaves, satellites, or a combination of communication channels.

Telephone company deregulation has encouraged a number of computers of companies to build their own wide area networks.

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Network Configuration

The configuration, or physical layout, of the equipment in a communication network is called topology.

Communication networks are usually configured in one or a combination of three patterns.

These configurations are star, bus, and ring networks.

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Star Network

A star network contains a central computer and one or more terminals or personal computers connected to it, forming a star.

A star network configuration is often used when the central computer contains all the data required to process the input from the terminals, Such as an airline reservation system.

A star network can be relatively efficient, and close control can be kept over the data processed on the network.

·314·23/4/21 计算机专业英语 314

A star network

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Bus Network

When a bus network is used, all the devices in the network are connected to a single cable.

Information is transmitted in either direction from any one personal computer to another.

An advantage of the bus network is that devices can be attached or detached from the network at any point without disturbing the rest of the network.

·316·23/4/21 计算机专业英语 316

A bus network

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Ring Network

A ring network does not use a centralized host computer. Rather, a circle of computers communicate with one another.

A ring network can be useful when the processing is not done at a central site, but at local sites.

An advantage of a ring network is that less cable is usually needed and therefore network cabling costs are lower.

·318·23/4/21 计算机专业英语 318

A ring network

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Connecting Networks

Sometimes you might want to connect separate network. You do this by using gateways and bridges.

A gateway is a combination of hardware and software that allows users on one network to access the resources on a different type of network.

A bridge is a combination of hardware and software that is used to connect similar networks.

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Key Words

accuracy 精确，正确channel 通道，频道classify 分类，归类common carriers 电信公司connection-oriented 面向连接的detach 使分离，分遣disadvantage 缺点establish 建立，确立gateway 网关geographic 地理的hierarchy 等级体系

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Key Words

inquiry 质询，探索misplace 放错地方multi-drop 多分支的，多点（网络）node 网络节点，连接到网络上的设备privately 私人地，秘密地reservation 保留，保留品scope 范围，广度topology 拓扑学，地志学

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Notes

[1] Network software consists of protocols, or rules by which processes can communicate.本句的“ or rules”作同位语，“ by which processes can communicate” 作宾语补足语。译文：网络软件由协议或过程通信的规则组成。[2] Information resource sharing allows anyone using a personal computer on the local area network to access data stored on any other computer in the network.本 句 中 的“ anyone” 作宾语 ，“ using a personal computer on the local area network”作“ anyone” 的定语，“ to access data”作宾语补足语。译为：信息资源共享允许局域网上每一个计算机用户访问存储于网上其他计算机中的数据。

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Notes

[3] A star network contains a central computer and one or more terminals or personal computers connected to it, forming a star.本句中的“ a central computer and one or more terminals or personal computers”作宾语。译为：星形网络由一台中央计算机和一台或多台连接到该中央计算机上并形成星形结构的终端或计算机组成。[4] Thus, one disadvantage of a ring network is that if one node fails, the entire network fails because the data does not get past the failed node.本句中的“ that”引导表语从句，“ if one node fails” 作条件状语，而“ because the data does not get past the failed node”作原因状语。译为：因此，环形网络的缺点是如果一个节点出现故障，由于数据不能通过出现故障的节点，就会使整个网络无法工作。

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Notes

[5] For example, if a company had similar but separate local area networks of personal computers in their accounting and marketing departments, the networks could be connected with a bridge.

本句由“ if”引导条件状语从句。译为：例如，某公司在其财务部和市场部各有一套由个人计算机组成的类似的但相互独立的局域网，这两个网络就可通过网桥连接起来。

·325·23/4/21 计算机专业英语 325

词组翻译练习

(1)  局域网 Local Area Network

(2)  广域网 Wide Area Network

(3)  通信 communication

(4)  物理布局 physical layout

(5)  环网 ring network

(6)  星型网络 star network

(7)  点对点 point to point

(8)  网关 gateway

·326·23/4/21 计算机专业英语 326

Reading Material ：Network Management

Good management delivers high service quality, high availability, and controls the costs of ownership (staffing, facilities, and upgrades).

Management tasks can be grouped into tactical and strategic categories. The most common framework depicted in Network management designs is

centered on the Open Systems Interconnect (OSI).

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Management Functional Areas

User Management—Accounting & Cost ManagementResource Management— (System Management & Management Functional Domains (MFDs))Configuration ManagementPerformance ManagementMaintenance—Security & Fault Management

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4.2 The OSI Reference Model

The OSI reference model, sometimes also called ISO or 7 layers reference model for communication.

This model describes the principles for interconnection of computer systems in an Open System Interconnection environment.

The general principle which leads to the definition of the OSI standard was to allow connection and communication between any computer systems as long as they comply with this “open” standard.

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The major principles

A layer should be created there a different level of abstraction is needed. Each layer should perform a well-defined function. The function of each layer should be chosen with an eye toward defining

internationally standardized protocols. The layer boundaries should be chosen to minimize the information flow across

the interfaces. The number of layers should be large enough so that distinct functions need

not be put together in the same layer without necessity, and small enough so that the architecture will not become out of control.

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The OSI Reference Model

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The Physical Layer

The physical layer defines network transmission media, signaling methods, bit synchronization, architecture (such as Ethernet or Token Ring), and cabling topologies.

The physical layer is concerned with transmitting raw bits over a communication channel.

The design issues here largely deal with mechanical, electrical and procedural interfacing to the subnet.

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The Data Link Layer

The task of the data link layer is to obtain a raw transmission facility and to transform it into a line that appears free of transmission errors to the network later.

It accomplished this task by breaking the input data up into data frames, transmitting the frames sequentially, and processing the acknowledgment frames sent back by the receiver.

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The Network Layer

The network layer controls the operation of subnet. It determines the chief characteristics of the node-host interface, and how

packets, the units of information exchanged in this layer, are routed within the subnet.

A major problem at this layer presented the issue of who is responsible for successful delivery of packets from end to end.

This layer also deals with the issue of congestion (bottleneck) as well as accounting i.e. packet statistics. IP and IPX are examples of network-layer protocols.

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The Transport Layer

The basic function of transport layer is to accept data from the session layer, split it up into smaller units, if necessary, pass these to the network layer, and ensure that the pieces all arrive correctly at the other end.

This layer is a true end-to-end layer. In other words, a program on the source machine carries on a conversation

with a similar program on the destination machine, using the message headers and control message.

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The Session Layer

The session layer defines how connections can be established, maintained, and terminated.

A session might be used to allow a user to log into a remote time-sharing system or to transfer a file between two machines.

The operation of setting up a session is often referred to as binding.

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The Presentation Layer

The presentation layer translates data to be transmitted by applications into a format suitable for transport over the network.

It performs certain transformations of data. The presentation layer could be designed to accept ASCII strings as input and

produce compressed bit patterns as output.

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The Application Layer

The application layer interfaces user applications with network functionality, controls how applications access the network, and generates error messages.

The application programs are responsible for hiding action of all levels below from a user (so called network transparency).

·338·23/4/21 计算机专业英语 338

Key Words

binding 绑定bottleneck 瓶颈buffer space 缓冲空间congestion 拥塞content 内容conversion 转换，转变decryption 解密encryption 加密术，密码术Ethernet 以太网incompatible 不兼容的

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Key Words

internationally 国际性地International Standard Organization 国际标准化组织negotiate 谈判，商议Open System Interconnection 开放系统互联recovery 恢复，复原reflect 反射，反映router 路由器session layer 会话层

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Key Words

split … up 把……分开，分裂synchronization 同步System Network Architecture 系统网络结构subnet 子网Token Ring 令牌环网transparency 透明，透明度transmitter 传送者vendor 供应商

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Notes

[1] The number of layers should be large enough so that distinct functions need not be put together in the same layer without necessity, and small enough so that the architecture will not become out of control.

本句的“ large enough” 和“ small enough” 都是“ be” 的表语，两部分表语后面都跟由“ so that”引导的目的状语从句作进一步的说明。译文：层次的数量应足够多以便使不同的功能不致于毫无必要地放在同一层次中，层次的数量还应足够少以便结构不会变得难以控制。

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Notes

[2] Typical questions here are how many volts should be used to represent an 1 and how many a 0, how many microseconds a bit occupies, whether transmission may proceed simultaneously in both directions, how to establish the initial connection and how to tear down the connection when both sides are finished, how many pins the network connector has and what kind of function each pin has.

这是一个典型的长句，本句主语是“ questions” ，系动词“ are”后面都是表语，表语是由“ how” 或“ whether”引导的若干部分组成。译文：此处典型的问题是用多少伏特表示 1 ，用多少伏特表示 0 ，每一比特占多少微秒，是否传输过程可以在两个方向上同时进行，怎样建立初始连接，当两边均已完成时怎样拆卸连接，网络连接器有多少管脚，每个管脚的功能如何。

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Notes

[3] Since the physical layer merely accepts and transmits a stream of bits without any regard to meaning or structure, it can create and recognize frame boundaries until the data link layer.

本句由“ Since”引导原因状语从句。译文：由于物理层只接收和传输比特流而不考虑意义和结构，所以直到数据链路层才产生和识别帧的边界。

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Notes

[4] What this layer of software does, basically, is to accept messages from the source host, convert them to packets, and observe the packets to get to the destination.

本句的“What this layer of software does” 是主语从句，“ basically” 是插入语，表语由若干个并列部分构成。译文：这层软件要做的基本上是从源主机接收信息，把它们转换成包，并监控着包传向目的地。[5] The transport layer sequences packets so that they can be reassembled at the destination in the proper order.

本句由“ so that”引导目的状语从句。译文：传输层排序数据包，以便数据包能够在目的地按照正确的顺序重新组合。

·345·23/4/21 计算机专业英语 345

词组翻译练习

(1)  物理层 physical layer

(2)  网络连接器 network connector

(3)  数据链路层 data link layer

(4)  动态方式 dynamic manner

(5)  网络透明度 network transparency

(6)  传输层 transport layer

(7)  远程分时系统 remote time-sharing system

(8)  非兼容文件格式 incompatible file format

·346·23/4/21 计算机专业英语 346

Reading Material ： TCP/IP

A protocol is a set of rules that describes, in technical terms, how something should be done.

TCP/IP is the common name for a collection of over 100 protocols that are used to connect computers and networks.

The actual name “TCP/IP” comes from the two most important protocols: TCP (Transmission Control Protocol) and IP (Internet Protocol).

In fact, the Internet runs so well that it may take only a few seconds to send a file from one host to another, even though they are thousands of miles apart and all the packets must pass through multiple computers.

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Internet Protocol

The IP packet provides the address necessary to get the data to the right Internet computer.

These addresses contain 32-bit number, ranging from zero to about 4.3billion. These IP addresses are usually written in a convenient shorthand, which is

called dotted-octet notation, or Dotted Decimal Notation. Once an IP packet has made its way to the right network, the routers in that

network can then route it to the right subnet, and finally to the designated computer.

·348·23/4/21 计算机专业英语 348

Transmission Control Protocol

TCP allows a process on one machine to send a steam of data to a process on another.

TCP provides two major services that are not included with IP—guaranteed delivery, and serialization of data which makes sure that data sent in one order arrives in the same order.

TCP uses sequence numbers to indicate the order in which data it is sending should appear, these sequence numbers increase by one, each time TCP puts data into a new IP packet.

·349·23/4/21 计算机专业英语 349

4.3 Internet Overview

Web Service How To Use Internet

·350·23/4/21 计算机专业英语 350

Web Service

The short-form of a Web Services definition is: “A set of standards that allow applications to talk to each other over the net.”

The “Services” part of Web Services is indicative of the service-oriented nature of application communications.

A service can combine multiple back-end application functions into what is known as a “composite application interface”.

·351·23/4/21 计算机专业英语 351

Web Service

Web Service interfaces are defined using XML in the form of a “schema” that describes the request and response data formats, types, and relationships.

Web Services technology supports increased operational efficiencies and improved service by allowing multiple applications to interoperate.

Now that we know a little more about Web Services, lets look at the two different scenarios mentioned above: intra-enterprise, where internal applications are involved; and inter-enterprise, where applications of different trading partners are involved.

·352·23/4/21 计算机专业英语 352

How To Use Internet

Most people connect to the Internet by using network connection or Internet service provider (ISP).

An ISP supplies a service number that you can dial from your computer to log on the Internet server.

With the communication tools included in Windows 2000, you can use your computer to send e-mail, handle phone calls, send a fax, or conduct a meeting with a video conference.

·353·23/4/21 计算机专业英语 353

How To Use Internet

With Internet Explorer and an Internet connection, you can search for and view information on the World Wide Web.

You can use Phone Dialer to place telephone calls or participate in video conference calls from your computer.

The Windows 2000 Telephony API (TAPI) allows you to configure dialing rules for all telephony applications.

·354·23/4/21 计算机专业英语 354

Key Words

browse 浏览compatibility 兼容性complexity 复杂，复杂性confidence 信心contract 合约，契约dial 拨号furnish 供给，提供generically 属类地，属类上infrastructure 基础结构，基础设施ISDN (Integrated Services digital Network) 综合服务数字网ISP (internet Server Provider) 互联网服务提供商kiosk 凉亭，报摊

·355·23/4/21 计算机专业英语 355

Key Words

longevity 长寿，寿命modem (modulation and demodulation) 调制解调器OSI （ Open System Interconnect Reference Model ） 开放式系统互联参考模型oversee 了望，监督proprietary 所有者，私有的reservation 保留，预定scenario 方案，情节schema 概要，图解workspace 工作区WWW (World Wide Web) 万维网

·356·23/4/21 计算机专业英语 356

Notes

[1] Windows 2000 provides you with quick and easy access to the Internet, no matter what programs you are running or tasks you are performing.

本句中 access作为名词，译为“访问”，名词 access后必须跟介词结合使用，表示“访问…”，或“进入…”之意。译为：不管正在运行何种程序或执行何种任务， Windows2000 使你能快速而方便地访问互联网。[2] The Active Desktop allows you to customize your workspace and the Address bar helps you to connect to the Internet from any window.

本句中 Active ， Desktop ， Address 单词首字母大写，是用于特指在 Windows 2000系统中的对象，并非通常意义上的事物。译为：活动桌面使你能定制工作环境，任一窗口中的地址条帮助你接入互联网。

·357·23/4/21 计算机专业英语 357

Notes

[3] Internet Explorer also lets you search the Internet for people, businesses, and information about subjects that interest you.本句中 that interest you 是由关系代词 that引出的后置定语从句，用于修饰 subjects 。译为： Internet Explorer 也使你能在互联网找人，查询某个企业，以及感兴趣的相关主题信息。[4] To completely configure dialing rules on a computer after installing Windows 2000, use Phone and Modem options in Control Panel.本 句 中 不 定 式 短 语 to completely configure dialing rules on a computer after installing Windows 2000作为表示目的的状语。译为：安装Windows 2000后，为了在计算机上完全设置好拨号限定，可用控制面板上的“电话机”和“调制解调器”选项实现。

·358·23/4/21 计算机专业英语 358

词组翻译练习

(1)  电话应用接口程序 TAPI (Telephony API)

(2)  文件服务器 file server

(3)  分布式网络 distributed network

(4)  集成网络 integrated network

(5)  帮助菜单 Help menu

(6)  面向服务的 service-oriented

(7)  视频会议 conference video

(8)  中间件 middleware

·359·23/4/21 计算机专业英语 359

Reading Material ： E-mail

E-mail refers to the transmission of messages over communications networks.

E-mail is used to send written messages between individuals or groups of individuals, often geographically separated by large distances.

E-mail is the basis of much organized exchange between groups of individuals.

Another use of e-mail is Usenet, in which discussions on a particular subject are grouped together into newsgroups.

·360·23/4/21 计算机专业英语 360

E-mail

E-mail uses the office memo paradigm in which a message contains a header that specifies the sender, recipients, and subject, followed by a body that contains the text of the message.

An E-mail address is a string divided into two parts by the @ character (pronounced as “at”). The first part is a mailbox identifier, and the second stands for the name of the computer on which the mailbox resides.

A mail exploder program uses a database of mailing lists to provide communication among large groups of participants.

·361·23/4/21 计算机专业英语 361

4.4 Internet Security

Any one responsible for the security of a trusted network will be concerned when connecting it to a distrusted network.

In the case of connections to the Internet this concern may be based largely on anecdotal evidence gleaned from widespread media coverage of security breaches.

A closer inspection of the facts and statistics behind some of the media coverage will, however, only serve to deepen that concern.

·362·23/4/21 计算机专业英语 362

Encryption techniques

Encryption is the way to solve the data security problem. There are two kinds of encryption techniques - symmetric key encryption and

asymmetric key encryption. For symmetric key encryption, both parties should have a consensus about a

secret encryption key. When A wants to send a message to B, A uses the secret key to encrypt the message. After receiving the encrypted message, B uses the same (or derived) secret key to decrypt the message.

For asymmetric key encryption, there is a pair of keys for each party: a public key and a private key.

·363·23/4/21 计算机专业英语 363

Digital certificate

Digital certificate is an identity card counterpart in the computer society. When a person wants to get a digital certificate, he generates his own key pair,

gives the public key as well as some proof of his identification to the Certificate Authority (CA).

CA will check the person's identification to assure the identity of the applicant.

·364·23/4/21 计算机专业英语 364

Digital Signature

A digital signature is an electronic signature that can be used to authenticate the identity of the sender of a message or the signer of a document, and possibly to ensure that the original content of the message or document that has been sent is unchanged.

A digital signature is a string of bits attached to an electronic document, which could be a word processing file or an e-mail message.

A digital signature can be used with any kind of message, whether it is encrypted or not, simply so that the receiver can be sure of the sender’s identity and that the message arrived intact.

·365·23/4/21 计算机专业英语 365

Firewall

A firewall is simply a group of components that collectively form a barrier between two networks.

The firewall device is a security system for connecting a computer network to other computer network.

One of the primary aims of the firewall is to achieve “wire speed” and be able to move billions of bits of data every second through the firewall.

However, the design of the firewall is more of a “switch”. The intermediate network between the two computer motherboards creates a dedicated dynamic “pipe” between the two points on which to transmit data from the IP to other IP side.

·366·23/4/21 计算机专业英语 366

Key Words

amalgam 混合，合成anecdotal 轶事的assert 主张，断言barrier 障碍，栅栏breach 破坏，违反CA(Certificate Authority) 证书授权机构consensus 合意，一致cryptography 密码系统，密码术cybermarket 网上商店decrypt 解密，解释明白distrust 不信任

·367·23/4/21 计算机专业英语 367

Key Words

firewall 防火墙glean 收集imitate 模仿，仿造inspection 检查，视察restrict 限制，约束signer 签名者time-stamp 时间戳up-to-date 最近的 , 当代的violation 违反，违背

·368·23/4/21 计算机专业英语 368

Notes

[1] The more people use Internet, the more concerns about Internet security.

“The more…, the more…” 是一个双重比较级的句子，相当于汉语的“……越多，……越多”译文：互联网使用的越多，对互联网的安全就关注的越多。[2] Almost all encryption schemes used in the Internet uses asymmetric key encryption for exchanging the symmetric encryption key, and symmetric encryption for better performance.

asymmetric key encryption 是指“非对称密钥加密”， symmetric key encryption 是指“对称密钥加密”译文：在互联网中几乎所有的加密方案都使用非对称密钥加密来替换对称加密密钥和对称加密，以得到更好的加密控制。

·369·23/4/21 计算机专业英语 369

Notes

[3] If the applicant is really the one “who claims to be”, CA will issue a digital certificate, with the applicant's name, e-mail address and the applicant's public key, which is also signed digitally with the CA's private key.

CA指“证书授权机构”，是可信任的第三方，它保证数字证书的有效性。 CA负责注册、颁发证书，并在证书包含的信息变得无效后删除（收回）证书。译文：如果申请人确如自己所声称的，证书授权机构将授予带有申请人姓名、电子邮件地址和申请人公钥的数字证书，并且该数字证书由证书授权机构用其私有密钥作了数字签名。

·370·23/4/21 计算机专业英语 370

Notes

[4] A digital signature can be used with any kind of message, whether it is encrypted or not, simply so that the receiver can be sure of the sender’s identity and that the message arrived intact.

本句由“ whether”引导让步状语从句，由“ so that”引导目的状语从句。译文：一个数字签名可以用于任何类型的信息，不论该信息是否加密，因此接收者能确信发送者的身份以及收到的信息完好无缺。[5] Since the advent of the Internet and computer network security, many people have sought for firewall.

本句由“ Since”引导原因状语从句。译文：自从互联网问世和网络安全的需要，许多人都在寻找防火墙。

·371·23/4/21 计算机专业英语 371

词组翻译练习

(1)  传统通信 traditional communication

(2)  对称密钥 symmetric key encryption

(3)  非对称密钥 asymmetric key encryption

(4)  公开密钥 public key

(5)  私有密钥 private key

(6)  数字认证 digital certificate

(7)  非授权通信 unauthorized communication

(8)  非授权访问 unauthorized access

·372·23/4/21 计算机专业英语 372

Reading Material ：Computer Security

Today, most computer facilities have some sort of security system. Computer users should be required to provide positive identification and

computer access should be controlled. Usually, authorized users are issued special cards, keys, passwords, or

account numbers. Another security problem concerns the protection of the operating system and

data on the computer. Security will continue to be a problem because the number of computers and

users continues to grow.

·373·23/4/21 计算机专业英语 373

4.5 E-commerce

E-commerce is doing business through electronic media. It means using simple, fast and low-cost electronic communications to

transact, without face-to-face meeting between the two parties of the transaction.

Electronic commerce is featured by these characters: fairness and freedom, high efficiency, globalization, virtualization, interactivity, autonomy, personalized service.

Electronic commerce will change the environment in which enterprises compete with each other and reduce costs which would otherwise be high in traditional market structure.

To ensure security of electronic commerce, an electronic certification center should be established.

·374·23/4/21 计算机专业英语 374

The features of Electronic Commerce

Space-time concept will change. The nature of market and the behavior of consumers change. Corporate credit and brand become treasured resources. Structure of enterprises will change from “pyramid” type to “flattened” type. Business mode in enterprises will change. Higher requirement of workers’ quality and technique. Material flow will be more important in electronic commerce than in usual

commerce. New recognition of information resource and attention resource.

·375·23/4/21 计算机专业英语 375

E-Commerce Strategies

The Web is adding new dimensions to conventional business practice and creating new types of business strategies.

As computer network facilitates information exchange in a speedy and inexpensive way, Internet now penetrates into almost every corner of the world.

Small and medium sized enterprises (SMEs) can forge global relationships with their trading partners everywhere in the world.

Businesses can sell goods to customers outside traditional markets, explore new markets and realize business opportunities more easily.

Companies must take advantage of customer information in their commerce models.

·376·23/4/21 计算机专业英语 376

Key Words

agency 代理机构，中介alteration 变更，改动brand 商标，品牌client 顾客，客户，当事人，委托人critical 批评的，临界的electronic invoice 电子发票encouragement 鼓励，奖励enterprise 企业globalization 全球化interactivity 交互性intermediary 中介，中介物

·377·23/4/21 计算机专业英语 377

Key Words

liaison 联络mutual 相互的，共有的notoriously 声名狼藉的，臭名昭著的obligation 义务，责任payment 付款，支付purchase 购买recognition 识别，承认recruiter 新会员，招募人员retailer 零售商scarcity 缺乏，不足survival 生存，幸存者virtualization 虚拟化

·378·23/4/21 计算机专业英语 378

Notes

[1] With the wide use of computer, the maturity and the wide adoption of Internet, the permeation of credit cards, the establishment of secure transaction agreement and the support and promotion by governments, the development of E-Commerce is becoming prosperous, with people starting to use electronic means as the media of doing business. maturity 意思是“成熟，完备，（票据）到期”， permeation愿意是“渗入，透过”，这里指信用卡的在社会中的普及， credit card 意思是“信用卡”。译文：随着计算机的广泛应用，互联网的日趋成熟和广泛利用，信用卡的普及，政府对安全交易协定的支持和促进，电子商务正变得繁荣起来，人们已开始利用电子媒介做生意。

·379·23/4/21 计算机专业英语 379

Notes

[2] Businesses can maintain their competitive advantage by establishing close contact with their customers and consumers at anytime through Internet by providing the latest information on products and services round the clock.

latest information 意思是“最新信息”， round the clock 意思是“二十四小时”。译文：通过在互联网上全天候地提供产品及服务的最新信息，商家可以与客户和消费者随时建立紧密联系来确保他们的竞争优势。

·380·23/4/21 计算机专业英语 380

Notes

[3] if you don't want to purchase, install, customize and take care of all the necessary hardware and software for running a website, you can outsource the task to web hosting companies.

if引导条件状语从句，修饰“ you can outsource the task to web hosting companies” 。outsource 意思是“外包”，这是互联网上常见的一种让他人有偿提供所需服务的方式。 web hosting company 意思是“虚拟主机服务公司”，是指提供虚拟网站服务业务的公司。译文：如果你不想购买、安装、定制和关心网站运行所必需的所有硬件和软件，你可以将这个任务外包给虚拟主机服务公司。

·381·23/4/21 计算机专业英语 381

Notes

[4] Many existing retailers have done a notoriously poor job of utilizing customer information to date.

本句中的“ utilizing customer information to date”作定语，修饰“ job” 。译文：很多现有的零售商在利用顾客信息方面做得极差。[5] In electronic commerce, producers contact with each other through Internet, starting from purchasing raw materials to sales of goods, so that efficiency can be improved and cost can be reduced.

本句的“ In electronic commerce” 是介词短语作状语，由“ so that”引导的是目的状语从句。译文：在电子商务中，生产厂商通过互联网互相联系，从购买原材料开始，直至货品销售，从而能够提高效率和降低成本。

·382·23/4/21 计算机专业英语 382

词组翻译练习

（ 1 ）信息技术 information technology

（ 2 ）电子商务 E-commerce

（ 3 ）电子媒介 electronic media

（ 4 ）面对面 face-to-face

（ 5 ）贸易伙伴 trading partner

（ 6 ）在线支付 on-line payment

（ 7 ）无线通信 wireless communication

（ 8 ）电子货币 electronic currency

·383·23/4/21 计算机专业英语 383

Reading material ： Development of Electronic Commerce in China

Exploration in electronic commerce, governmental and civil, began in 1993 in China.

The ministry of Foreign trade set up in February 1996 China Electronic Commerce Center responsible for research, construction, and operation of international electronic commerce project in China.

In March 1999, the Ministry of Information Industry approved the electronic commercial network of pharmaceutics and health as a model project of electronic commerce for all trades.

·384·23/4/21 计算机专业英语 384

Development of Electronic Commerce in China

In April 2000, sponsored by the Ministry of Information Industry, National Economy and Trade Commission, and China Council for Promotion of International Trade, the 4th China International Electronic Commerce Conference was held.

Although developing rapidly and seeming to have brilliant prospects, electronic commerce faces a series of real problems, for example, tax system, conception, protection of privacy, infrastructure, etc.

·385·23/4/21 计算机专业英语 385

第 5 章 Computer Applications

5.1 Word Processing

5.2 Multimedia

5.3 Computer Graphics

5.4 Database Applications

5.5 Computer Virus

·386·23/4/21 计算机专业英语 386

5.1 Word Processing

Personal computer-based office automation software has become an indispensable part of electronic management in many countries.

Word processing programs have replaced typewriters; spreadsheet programs have replaced ledger books; database programs have replaced paper-based electoral rolls, inventories and staff lists; personal organizer programs have replaced paper diaries; and so on.

Word processing refers to the methods and procedures involved in using a computer to create, edit, and print documents.

Word processing software has replaced typewriters for producing documents such as reports, letters, papers, and manuscripts.

·387·23/4/21 计算机专业英语 387

The advantage of word processing

The great advantage of word processing over using a typewriter is that you can make changes without retyping the entire document.

If you want to delete a paragraph, you simply remove it, without leaving a trace. It is equally easy to insert a word, sentence, or paragraph in the middle of a

document. Word processors also make it easy to move sections of text from one place to

another within a document, or between documents. Most standard word processing features are supported, including footnotes

and mail-merge but no tables or columns. The interface uses customizable toolbars, and the editing screen is a zoom-able

draft mode that optionally displays headers, footnotes, and footers.

·388·23/4/21 计算机专业英语 388

Microsoft Word

Microsoft Word is a powerful word processing application that will allow you, through simple keystroke and menu navigation, to create dynamic documents for work, school, or personal use.

Word processors vary considerably, but all word processors support some basic features.

·389·23/4/21 计算机专业英语 389

Full-featured word processors usually support the following features

Insert and Delete text Cut, paste and copy Page size and margins Search and replace Word wrap Print File management Font specifications Footnotes and cross-references

·390·23/4/21 计算机专业英语 390

Full-featured word processors usually support the following features

Graphics Headers, footers and page numbering Layout Macros Merge Spell checker Tables of contents and indexes Thesaurus Windows WYSIWYG(What You See Is What You Get)

·391·23/4/21 计算机专业英语 391

Key Words

browser 浏览器collaborate 合作，勾结considerable 相当的，重要的customized 定制的footnote 脚注hardcopy 硬拷贝indispensable 不可缺少的，绝对必要的italic 斜体字，斜体的ledger 分类帐managerial 管理的memo 备忘录novel 小说，长篇故事

·392·23/4/21 计算机专业英语 392

Key Words

paragraph 段落proficiently 精通地，熟练地readiness 预备，准备readjust 重新调整，再调整reuse 再使用synonym 同义词thesaurus 词典typeface 字体typewriter 打字机underline 下划线utility 实用程序

·393·23/4/21 计算机专业英语 393

Notes

[1] To perform word processing, you need a computer, a special program called a word processor, and a printer.“To perform word processing” 作 目 的 状语，“ computer” 、“ program” 和“ printer”并列作宾语。译文：为实现文字处理，需要一台计算机，一种称作文字处理器的专用软件，还有一台打印机。[2] Microsoft Word is a powerful word processing application that will allow you, through simple keystroke and menu navigation, to create dynamic documents for work, school, or personal use.本句的“ allow”可作为“允许”理解，但是从汉语的角度来说，可以理解为“让、使”，也就是像“make, let” 的含义。“ that will …”引导定语从句，修饰“ word processing application” 。译文： Microsoft Word 是一款功能强大的字处理软件，通过简单的键盘输入以及菜单导航，你将能为工作、学习或者个人使用创建动态的文档。

·394·23/4/21 计算机专业英语 394

Notes

[3] The word processor automatically keeps track of page numbers so that the correct number appears on each page.

由“ so that”引导的部分作目的状语。译文：软件还会自动跟踪页码，以保证每一页上的页码准确无误。[4] The ability to define macros allows you to save yourself a lot of time by replacing common combinations of keystrokes.

本句的“ to define macros”作定语，修饰“ The ability” ，“ to save yourself a lot of time”作宾语，由“ by”引导的部分作状语。译文：定义宏可以节省大量时间，因为宏取代了一些常用的键盘操作序列。

·395·23/4/21 计算机专业英语 395

Notes

[5] This is particularly valuable when working on a large project that consists of several different files.

“when working on a large project” 是 状 语 ，“ that consists of several different files”作定语，修饰“ project” 。译文：这一功能在处理含有多个不同文件的大项目时特别有价值。

·396·23/4/21 计算机专业英语 396

词组翻译练习

(1)  通信技术 communication technology

(2)  办公自动化 office automation

(3)  电子表格程序 spreadsheet

(4)  研究报告 research report

(5)  拼写检查 spell check

(6)  邮件合并 mail-merge

(7)  插入和删除文本 insert and delete text

(8)  全功能字处理器 full-featured word processor

·397·23/4/21 计算机专业英语 397

Reading Material ： Office Automation

Today’s organizations have a wide variety of office automation hardware and software components at their disposal.

Modern office automation software is very powerful. Skilled users can develop very sophisticated products.

The fast pace of modern business requires critical information quickly. At the same time, government demands and business bureaucracy require extensive amounts of paperwork.

·398·23/4/21 计算机专业英语 398

Desktop Publishing

In all organizations, there is the fundamental need to produce written communications that not only deliver the company’s message clearly but have a professional look as well.

Desktop publishing can satisfy that need. In its simplest form, desktop publishing entails the use of personal computers

to prepare and print a wide variety of typeset-or near-typeset-quality documents.

·399·23/4/21 计算机专业英语 399

Video Conferencing

Video conferencing involves the linking of remote sites by one-way or two-way television.

Many businesses are experimenting with sales and board meetings through video conferencing.

The cost is still high, especially if the video conference involves a direct two-way satellite channel connection.

·400·23/4/21 计算机专业英语 400

Videotext

Videotext is a form of electronic publishing that consists of a database connected to terminals or personal computers.

Offices using videotext can electronically publish standard operating procedure manuals, sales literature, in-house newsletters, company wide phone lists, and other information that is subject to periodic change.

·401·23/4/21 计算机专业英语 401

5.2 Multimedia

Multimedia is any combination of text, graphic art, sound, animation, and video delivered to you by computer or other electronic means.

There is increasing emphasis on communications capabilities and sharing information over networks such as the Internet.

Multimedia is made possible and affordable today because of increases in storage and speed and decreases in size and cost; this yields an increase in performance and availability.

·402·23/4/21 计算机专业英语 402

Important Considerations

Storage: Permanent storage is used to keep digitized information for future retrieval and use. Multimedia requires huge amounts of storage during both the development and application stages. Many multimedia products require storage on a CD-ROM.

Bandwidth: Bandwidth can be thought of as the pipe through which information must be pumped. The larger amount of data that needs to be delivered, the larger the pipe needs to be. This is currently the biggest limitation to delivering large amounts of digital video in multimedia. Optical fiber provides one of the largest pipes available.

·403·23/4/21 计算机专业英语 403

Important Considerations

Processor speed: The processor speed is the ability of the computer to perform operations quickly. Because of the large amount of data required for sound and video, multimedia requires a fast processor speed.[1]

Display depth: The display depth is the ability of the display screen to project an accurate and rich image. Newer computers can display millions of colors and approach photo realistic images.

·404·23/4/21 计算机专业英语 404

Multimedia Equipment

Multimedia requires sound and graphics capability. A speedy processor chip plus a CD-ROM drive or DVD drive are also desirable.

A fast processor can quickly handle the huge amount of digital data that is required to store and produce multimedia.

A sound card gives a computer the capability to record and play sound files as well as video sound tracks.

A CD-ROM drive allows your computer to access audio and software CD-ROMs. Multimedia elements—especially videos—require lots of storage space.

·405·23/4/21 计算机专业英语 405

Multimedia Application

Computer-Based Training (CBT) Education Edutainment Entertainment Information Access Business Presentations

·406·23/4/21 计算机专业英语 406

Key Words

abundance 丰富，冗余accelerated 加快的affordable 负担得起的animation 激励，活泼category 种类，类项consideration 考虑，原因consult 商量，协商definitely 明确地emergency 紧急entertainment 娱乐essence 实质，本质feasible 可行的，适宜的

·407·23/4/21 计算机专业英语 407

Key Words

hybrid 混合的hypermedia 超媒体limitation 限制literally 不夸张地multimedia 多媒体overwhelm 制服，压倒phenomenon 现象，迹象pump 抽吸resistance 抵抗力，反抗sprinkle 洒，散synthesis 合成yield 出产，生产

·408·23/4/21 计算机专业英语 408

Notes

[1] Because of the large amount of data required for sound and video, multimedia requires a fast processor speed.

本句由“ Because of”引导原因状语，主语是“multimedia” 。译文：由于声音和视频需要大量的数据，所以多媒体需要一个快的处理器速度。[2] By using a multimedia application, the company found it has saved expenses and trained employees more effectively than anything else it had tried.

本句由“ by”引导方式状语从句。译文：通过使用多媒体，公司发现它既节省开支又比其它培训员工的方法有效。。

·409·23/4/21 计算机专业英语 409

Notes

[3] Multimedia uses the computer to integrate and control diverse electronic media such as computer screens, videodisk players, CD-ROM disks, and speech and audio synthesizers.

such as 意思是“比如，诸如，例如”， synthesizer 意思是“合成器”译文：多媒体技术使用计算机集成并控制各种电子介质，如计算机屏幕，视频盘控制器， CD-ROM盘，以及语音和音频合成器。[4] Multimedia capabilities will be sprinkled through almost all layers of software, offering new interfaces, new business applications, redefined programming tools, and possibly new operating systems.

sprinkle 意思是“撒，洒，把…撒在”， programming tools指“程序设计工具”。译文：多媒体的能力将散布在软件的几乎所有层次之中，提供新的接口，新的商业应用，重新定义程序设计工具，甚至可能定义新的操作系统。

·410·23/4/21 计算机专业英语 410

Notes

[5] Object-oriented programming will grow to include more media-rich objects; programming tools will offer diagrammatic control of code.

object-oriented 意思是“面向对象的”， diagrammatic 意思是“图解的，图表的”。译文：面向对象的程序设计将不断发展直至包含更多的富有媒体的对象；程序设计工具提供图表式的代码控制。

·411·23/4/21 计算机专业英语 411

词组翻译练习

（ 1 ）全彩色图像 full-color image

（ 2 ）标准设备 standard equipment

（ 3 ）图形技术 graphics technology

（ 4 ）动画 animation

（ 5 ）光纤 optical fiber

（ 6 ）光盘驱动器 optical disk driver

（ 7 ）编程工具 programming tools

（ 8 ）多媒体辅助工具 multimedia-assisted tools

·412·23/4/21 计算机专业英语 412

Reading material ： Multimedia Software

PowerPoint Flash Authorware Graphics Software

·413·23/4/21 计算机专业英语 413

PowerPoint

PowerPoint is multimedia display software, is one component of Office suite software. It provides means for making multimedia display.

PowerPoint has very strong functions for making slides. Using “view” button, PowerPoint can perform view switching. Regardless of

what view is selected, contents of the display file will not change. PowerPoint provided five views.

Common view, Outline view, Slide view, Overlook view and Projection of slides.

·414·23/4/21 计算机专业英语 414

Flash

Macromedia’s Flash is a powerful software package that enables web developers to create engaging web content.

Flash movies are interactive vector graphics and animation for web sites. Flash allows you to combine sound, motion, and interactively to create

stunning web interfaces and animations. Flash is a handy tool for illustrating instructional concepts. Interactive study guides can be created with Flash.

·415·23/4/21 计算机专业英语 415

Authorware

Authorware is the multimedia making software that is put out by Macromedia Company.

Authorware adopts the object-oriented programming and it is a kind of multimedia developing instrument on the basis of icon and process line.

It has already applied in school teaching, enterprise training, various kinds of demonstrations of the reports, commercial field, and so on.

·416·23/4/21 计算机专业英语 416

Graphics Software

Graphics software helps you create, edit and manipulate images. These images could be photographs that you are planning to insert in a

brochure, a freehand portrait, a detailed engineering drawing, or a cartoon animation.

If you have artistic talent you want to use a computer to create paintings, sketches and other images, you can use paint software to create and edit bitmap images.

3D graphics software helps you to create a wire-frame that represents a three-dimensional object.

·417·23/4/21 计算机专业英语 417

5.3 Computer Graphics

The use of computer graphics pervades many diverse fields. Applications range from the production of charts and graphs, to the generation

of realistic images for television and motion pictures to the interactive design of mechanical parts.

Computer graphics includes the design of hardware such as displays, the algorithms that are necessary to generate lines on these displays, the software that is used by both the graphics-system programmer and the application programmer, and the applications of computer-generated images.

·418·23/4/21 计算机专业英语 418

Design

The designer will then use the input device to select and move the desired elements into the design and to make connections between elements.

To form this initial design, the system makes sophisticated use of computer graphics.

Circuit elements are drawn, and perhaps are moved about the screen. The circuit will be tested by an analysis program, which will display its results

on the workstation.

·419·23/4/21 计算机专业英语 419

Representing Graphics

Obviously, computers cannot store and transmit graphics using character representation codes such as ASCII.

Nevertheless, they must somehow encode graphics as 1s and 0s to store and transmit them electronically.

There are two very different approaches to encoding graphics for computer system: bitmap and vector.

·420·23/4/21 计算机专业英语 420

Bitmap Graphics and Vector Graphics

Computer store bitmap images, such as digital photos, using a code that indicates the state of each individual dot, or pixel, displayed on the screen.

Bitmap graphics range from simple black-and-white images to full-color photographic-quality images.

When you create a vector graphic, you draw lines and shapes in various colors. The computer then translates these lines and shapes into a set of instructions

that can recreate your graphic.

·421·23/4/21 计算机专业英语 421

Application of Computer Graphics

Computer graphics is used today in many different areas of industry, business, government, education, entertainment, and, most recently, in the home.

Computer graphics is used for the production of highly accurate representation on paper or film of geographical maps, relief maps, exploration maps for drilling and mining, oceanographic charts, weather maps, contour maps, oil exploration maps, and population density maps.

In computer-aided design (CAD), interactive graphics is used to design components and systems of mechanical, electrical, electro-mechanical and electronic device.

·422·23/4/21 计算机专业英语 422

Application of Computer Graphics

Computer-produced animated movies of the time-varying behavior of real or simulated objects are becoming increasingly popular.

The use of alphanumeric and graphic terminals to create and disseminate information in the office and even the home is increasing rapidly.

Computer art and advertising have the common goal of expressing a “message” and attracting the attention of the public with aesthetically pleasing pictures.

·423·23/4/21 计算机专业英语 423

Key Words

aesthetically 美学地，审美地alphanumeric 字母数字的aspect 外观，方面contour 轮廓deformation 损形，变形disseminate 散播，宣传drilling 演练enormous 巨大的，庞大的exploration 探测，勘测

·424·23/4/21 计算机专业英语 424

Key Words

hull 壳，船体hydraulic 水力的，水压的mechanical 机械的，力学的nuclear 核的，原子能的oceanographic 海洋图形学organ 器官pictorially 形象化地physiological 生理学上的

·425·23/4/21 计算机专业英语 425

Key Words

realistic 现实的，逼真的relief 减轻，解除render 回报，返还routinely 日常地，惯例地shadow 阴影，影像thermal 热的，热量的

·426·23/4/21 计算机专业英语 426

Notes

[1] The designer is seated at a graphics workstation with a graphical input device, such as a mouse, with which she can indicate locations on the display.句中的“ such as a mouse” 是同位语，“ with a graphical…”作宾语补足语。译文：设计者坐在带有图形输入设备的图形工作站前，如用鼠标确定显示的位置。[2] Now the designer can modify the design as necessary, try another design, or accept what has already been done.本句的谓语动词有三个，“modify” 、“ try” 和“ accept” ，该句可以拆成三句。译文：现在设计者可视需要修改设计，尝试另一种设计，或者接受已经完成的设计。

·427·23/4/21 计算机专业英语 427

Notes

[3] The simplest bitmap image is a monochrome graphic, which contains only the colors white and black.

句中由“ which”引导非限定性定语从句。译文：最简单的位图图像是单色图像，仅有黑、白两色。[4] The computer then translates these lines and shapes into a set of instructions that can recreate your graphic.

本句由“ that”引导定语从句，修饰“ instructions” 。译文：然后计算机将这些线条和图形转换为能重构图像的指令。

·428·23/4/21 计算机专业英语 428

Notes

[5] Simulators generate views not only of the fixed world in which the vehicle is moving, but also of special effects such as clouds, fog, smoke, night-time lights, and other craft of various sizes and shapes, each on its own course.

这 是 一 个 长 句 ， 主 句 是“ Simulators generate views” ， 主 语 是“ Simulators” ，用“ not only…but also” 结构给出并列的定语，修饰宾语“ views” 。译文：模拟器产生的画面不仅包括车辆在其中移动的固有的世界，而且还有一些特殊效果，如云、雾、烟、夜光，以及其沿着自己航线飞行的各种大小和形状的飞行器。

·429·23/4/21 计算机专业英语 429

词组翻译练习

（ 1 ）计算机图形学 computer graphics

（ 2 ）图形程序 graphics program

（ 3 ）图像质量 image quality

（ 4 ）位图图像 bitmap image

（ 5 ）矢量图形 vector graphics

（ 6 ）数学模型 mathematical model

（ 7 ）高技术领域 high-technology area

（ 8 ）交互式卡通 interactive cartoon

·430·23/4/21 计算机专业英语 430

Reading Material ： Digital Images

Computational image processing can be defined as the operation of mathematical functions on numeric representations of pictorial scenes.

In general it is part of an overall process of visual perception, pattern recognition and image understanding.

The term digital image processing generally refers to processing of a two-dimensional picture by a digital computer.

·431·23/4/21 计算机专业英语 431

Image Formation

Images are formed either by reflection or transmission, in the first case a typical example is an object illuminated by visible light and recorded with a camera.

The geometry of the resultant image is governed by the general translation of a 3D object (world coordinates) to a 2D scene (camera coordinates).

Transmission images, on the other hand, result from the passage of radiation through an object.

·432·23/4/21 计算机专业英语 432

Image Data File Format

Type Usage

*.TIF DOS ， UNIX ， and Macintosh images

*.EPS Publishing industry format

*.GIF CompuServe graphics format

*.BMP Macintosh Windows format

*.BMP IBM OS/2 bit-mapped format

*.PICT Apple Macintosh images

·433·23/4/21 计算机专业英语 433

Image compression

There are two general types of compression: lossless and lossy. Lossless compression means that you can achieve a certain compression

factor and be able to exactly reproduce the original image. Lossy compression on the other hand allows some loss, but has the potential

for much higher compression rates.

·434·23/4/21 计算机专业英语 434

Types of Images

Images can be classified as either vector graphics or as bitmaps. You create vector graphics or line art when you create a chart in Excel or use

software such as CorelDraw which keeps track of objects such as lines, shapes or text blocks.

Bitmapped (raster) images are graphic images comprised of a series of pixels. A pixel or picture element is the basic unit of output.

·435·23/4/21 计算机专业英语 435

5.4 Database Applications Database systems are designed to manage large bodies of information. The management of data involves both the definition of structures for the

storage of information and the provision of mechanisms for the manipulation of information.

A database-management system (DBMS) consists of a collection of interrelated data and a set of programs to access those data.

The primary goal of a DBMS is to provide an environment that is both convenient and efficient to use in retrieving and storing database information.

·436·23/4/21 计算机专业英语 436

Transaction Management

A transaction is a collection of operations that performs a single logical function in a database application. Each transaction is a unit of both atomicity and consistency.

Thus, we require that transactions do not violate any database-consistency constraints.

In the absence of failures, all transactions complete successfully, and atomicity is achieved easily.

·437·23/4/21 计算机专业英语 437

Storage Management

Database typically require a large amount of storage space. Corporate databases are usually measured in terms of gigabytes or, for the

largest databases, terabytes of data. The performance of a system depends on what the efficiency is of the data

structures used to represent the data in the database, and on how efficiently the system is able to operate on these data structures.

·438·23/4/21 计算机专业英语 438

Database Administrator

The person who has such central control over the system is called the database administrator (DBA).

The DBA creates the original database schema by writing a set of definitions that is translated by the DDL compiler to a set of tables that is stored permanently in the data dictionary.

The DBA also creates appropriate storage structures and access methods by writing a set of definitions, which is translated by the data-storage and data-definition-language compiler.

·439·23/4/21 计算机专业英语 439

Today's Database Landscape

In addition to the development of the relational database model, two technologies led to the rapid growth of what are now called client/server database systems.

Because processing is split between client computers and a database server, this new breed of application was a radical change from mainframe-based application programming.

The second important technology was the local area network (LAN) and its integration into offices across the world.

·440·23/4/21 计算机专业英语 440

Distributed Database System

In a distributed database system, the database is stored on several computers. The computers in a distributed system communicate with one another through

various communication media, such as high-speed networks or telephone lines.

The computers in a distributed system are referred to by a number of different names, such as sites or nodes, depending on the context in which they are mentioned.

·441·23/4/21 计算机专业英语 441

Key Words

accustomed 惯常，习惯了的atomicity 原子数，原子性breed 种类，品种burden 担子，责任consistency 一致性corporate 社团的，合作的elsewhere 在别处impetrative 祈求，恳求inexpensive 便宜的，不贵重的minimize 最小化occurrence 发生，出现

·442·23/4/21 计算机专业英语 442

Key Words

radical 词根，基础relational 关系的，关联的relative 有关系的responsibility 责任，职责restore 恢复temporarily 暂时，临时terminate 结束，终止thereof 由此，关于……transaction 交易，和解协议

·443·23/4/21 计算机专业英语 443

Notes

[1] In addition, the database system must provide for the safety of the information stored, despite system crashes or attempts at unauthorized access.

此句中“ despite”引导的是让步状语从句。译文：另外，数据库系统还必须提供所存储信息的安全性保证，即使在系统崩溃或有人企图越权访问时也应保障信息的安全性。[2] The goal of a database system is to simplify and facilitate access to data.

句中的“ a database system”作定语，修饰主语“ the goal” ，“ to simplify…” 是不定式短语作表语。译文：数据库系统的目标是要简化和辅助数据访问，

·444·23/4/21 计算机专业英语 444

Notes

[3] If the response time for a request is too long, the value of the system is diminished.

本句中，“ If the response time for a request is too long”做条件状语从句。译文：如果一个要求的响应速度太慢，系统的价值就会下降。[4] The DBA creates the original database schema by writing a set of definitions that is translated by the DDL compiler to a set of tables that is stored permanently in the data dictionary.

本句中，“ that is translated by ……”做定语，修饰“ definitions” ，“ that is stored permanently in the data dictionary”做“ tables” 的定语。译文： DBA 通过书写一系列的定义来创建最初的数据库模式，这些定义被 DDL编译器翻译成永久地存储在数据字典中的表集合。

·445·23/4/21 计算机专业英语 445

Notes

[5] The main differences between shared-nothing parallel databases and distributed databases are that distributed database are typically geographically separated, are separately administered, and have a slower interconnection.

这是一个比较长的句子，本句的主语是“ differences” ，由“ between…and”连接的两个并列成分作定语，修饰主语，“ that distributed…”作表语。译文：无共享地并行数据库与分布式数据库之间的主要区别在于，分布式数据库一般是地理上分开的，分别管理的，并且是以较低的速度互相连接的。

·446·23/4/21 计算机专业英语 446

词组翻译练习

(1)  数据库管理系统 database management system

(2)  数据定义语言 data definition language

(3)  数据字典 data dictionary

(4)  分布式数据库系统 distributed database system

(5)  关系数据库模型 relational database model

(6)  数据库管理员 database administrator

(7)  程序员 programmer

(8)  客户 /服务器 client/server

·447·23/4/21 计算机专业英语 447

Reading Material ： Data Warehousing

A data warehouse is a repository (or archive) of information gathered from multiple sources, stored under a unified schema, at a single site.

Once gathered, the data are stored for a long time, permitting access to historical data.

Moreover, by accessing information for decision support from a data warehouse, the decision maker ensures that on-line transaction-processing systems are not affected by the decision-support workload.

·448·23/4/21 计算机专业英语 448

Data-warehouse architecture

·449·23/4/21 计算机专业英语 449

Data-warehouse strategy

When and how to gather data. What schema to use. How to propagate updates. What data to summarize.

·450·23/4/21 计算机专业英语 450

5.5 Computer Virus

A computer virus is a program designed to replicate and spread on its own, generally with the victim being oblivious to its existence.

Computer viruses spread by attaching themselves to other programs (e.g., word processor or spreadsheet application files) or to the boot sector of a disk.

Because a virus is software code, it can transmitted along with any legitimate software that enters your environment.

Nearly three-quarters (75 percent) of infections occurred in a networked environment, making rapid spread a serious risk.

·451·23/4/21 计算机专业英语 451

What’s the Features of Computer Virus?

Computer virus as a procedure can duplicate itself to other normal procedures or on some components of the system, for example, leading portion of disk.

The virus hidden in the infected system does not break out immediately; instead, it needs certain time or some conditions before it breaks out.

Virus will begin attack once some conditions are ready. Destruction caused by computer virus is extensive, it not only damages

computer system, deletes files, or alters data, etc., it can also occupies system resources, disturb machine operation, etc.

·452·23/4/21 计算机专业英语 452

What’s the Features of Computer Virus?

Typically, virus can infect several thousand computers in several hours if the infected microcomputer is linked with Internet.

On one hand, new virus or their variations emerge with each passing day; on the other hand, some virus may resurrect after they have been eliminated, for example, when the infected floppy disk are reused.

·453·23/4/21 计算机专业英语 453

What’s the Features of Computer Virus?

Virus can transmit normal information as a carrier and thus avoid our protective measures set in the system.

Virus infects through various ways beyond our control, in addition, as illegal duplication and pirate software get popular, detection of virus becomes very difficult.

Virus tends to hide itself to avoid being detected.

·454·23/4/21 计算机专业英语 454

What’s the Structure of Computer Virus?

Infected sign is also called virus signature composed of ASCII code of some numbers or characters.

Infecting module performs three tasks: To search for an executable file or covered file, to check if there is infected sign on that file, and to infect it, write virus code into the host procedure, if no infected sign is found.

The virus designer attempts in the destructive code to delete files, delete data, format floppy disk and hard disk, decrease computer efficiency and space, etc.

·455·23/4/21 计算机专业英语 455

What’s the Structure of Computer Virus?

If the condition is ready, the triggering module returns “true” value, and calls destroying module to destroy, otherwise it returns a “false” value.

Major control module controls the four modules mentioned above. Besides, it also ensures the infected program can continue to work normally and no deadlock will occur in contingency.

·456·23/4/21 计算机专业英语 456

What damage Can Viruses Do?

Some viruses are merely annoying, and others are disastrous. At the very least, viruses expand file size and slow real-time interaction,

hindering performance of your machine. Other viruses are more dangerous. They can continually modify or destroy data, intercept input/output devices,

overwrite files and reformat hard disks.

·457·23/4/21 计算机专业英语 457

What Are the Symptoms of Virus Infection?

Changes in the length of programs Changes in the file date or time stamp Longer program load time Slower system operation Reduced memory or disk space Bad sectors on your floppy

·458·23/4/21 计算机专业英语 458

What Are the Symptoms of Virus Infection?

Unusual error messages Unusual screen activity Failed program execution Failed system boot-ups when booting or accidentally booting from the A

drive Unexpected writes to a drive

·459·23/4/21 计算机专业英语 459

What Are the Effects of Computer Virus to the Society?

Some viruses create disgust effects or frighten the user, such as interfering the keyboard or displaying disgusting messages or pictures.

Computer viruses can be a great threat to a company. A company may lose important documents which may mean the lost of capital.

One step further, the operation breakdown of companies causes prelims to the society’s normal operation.

·460·23/4/21 计算机专业英语 460

Key Words

activate 使活动，使激活annoy 使恼怒，骚扰benign 良性的，善良的catastrophic 悲惨的，灾难的contingency 偶然性，可能性deadlock 死锁detect 发现，探测disastrous 损失惨重的，悲惨的disgust 厌恶，嫌恶eliminate 去除，排除intercept 截取，妨碍

·461·23/4/21 计算机专业英语 461

Key Words latency 潜伏，潜在legitimate 合法的，正当的lurk 潜伏，暗藏oblivious 遗忘的，健忘的paralyze 使瘫痪，使麻痹pirate 盗版，翻印preset 事先调整proliferate 扩散，增值resurrect 复活，复兴symptom 征候，症状triggerability 触发性variation 变更，变化victim 受害人，牺牲者

·462·23/4/21 计算机专业英语 462

Notes

[1] What makes viruses dangerous is their ability to perform an event.

本句的“What makes viruses dangerous”作主语从句。译文：计算机病毒之所以危险，是因为它们可以制造事端。[2] Computer virus usually comprises five components, infected sign, infecting module, destroying module, triggering module and main control module.

本句的“ infected sign, infecting module, destroying module, triggering module and main control module”作“ five components” 的同位语。译文：计算机病毒通常由五部分构成：感染符、传染模块、破坏模块、触发模块和主要控制模块。

·463·23/4/21 计算机专业英语 463

Notes

[3] Many virus writers seek only to infect systems, not to damage them, so their viruses do not inflict intentional harm.

本句的“ so their…” 是结果状语。译文：许多病毒作者仅仅是为了感染系统，并不想搞破坏，因此他们制作的病毒并不蓄意加害。[4] This will trigger chain reactions such that time will also be spent, so as money.

本句中的“ so as money”独立成句，省略了谓语，补充完整应该是“ so money will be spent also” 。因为“money” 与“ time” 谓语要表达的意思相同，因此用“ as”替代了谓语部分，并倒装在主语“money”之前。译文： 这会引发一连串的反应，如时间和金钱的浪费。

·464·23/4/21 计算机专业英语 464

Notes

[5] Since time means money, a great loss of money is likely to occur.

本句由“ Since”引导原因状语从句。一般“ Since” 在句首有两种意思，一种是表示原因，翻译为“因为，既然”，是陈述一般的既定原因，语气不如“ because” 强烈。另一种是表示时间，与句子的完成时态连用，表示“自从，自……以后”。译文：因为时间代表金钱，因此金钱的大量流失就很有可能会发生。

·465·23/4/21 计算机专业英语 465

词组翻译练习

(1)  计算机病毒 computer virus

(2)  被感染文件 infected file

(3)  感染模块 infecting module

(4)  可执行文件 executable file

(5)  病毒代码 virus code

(6)  触发条件 triggering condition

(7)  良性病毒 benign virus

(8)  防病毒工具 anti-virus tool

·466·23/4/21 计算机专业英语 466

Reading Material ：Classification of Computer Virus

By parasitism, computer virus can be classified into directing virus, file virus and hybrid virus.

The boot sector virus infects floppy disks and hard disks by inserting itself into the boot sector (for the hard disk, including also the Master Boot Record) of the disk, which contains code that’s executed during the system boot process.

File viruses infect files by attaching themselves to a file, generally an executable file with file extensions such as EXE and COM.

Hybrid viruses combine the ugliest features of both file and boot sector/partition table viruses.

·467·23/4/21 计算机专业英语 467

Reading Material ：Classification of Computer Virus

In the view of consequence, computer virus can be divided into “benign” virus and “malignant” virus.

The “benign” virus will destroy data or programs but will not paralyze the computer system.

“Malignant” virus will destroy data and system, resulting in paralysation of the whole computer, for example, CHI virus, “porch” virus.